Has Science lost its way?

[xelasnave]

Really has science lost its way. :question:
I mean no one sticks a knitting needle behind their eye like Newton if doing research on the optic nerve. Instead they use some fancy computer model that does not even include a needle. :eyepop::D
And all these thought experiments.
Once if you wanted to find out if a cat was dead in a box you just had to have a sniff but now days no. They dont use a real box or a real cat. :D
And there is concern from those who have obtained a good education on the net. :rolleyes: that their contributions via better theories are not treated with the respect given to similar scientists at CERN or NASA. ;);):DWhy does the mainstream support the big bang theory as if it was the be all and end all when after all it is just a theory. :rolleyes::P:D
If they just looked at their "quantum theory" they would realise anything is possible. :screwy::P;)
They try and make it an exclusive club expecting you to have a fancy degree from some fancy University. :shrug::P
So what is going wrong.
Do you know they wont fund UFO research and just think how much we could learn from the aliens. They wont even believe all the sightings recorded on utube. :rolleyes::lol:
What do you think can be done to get science back on track? :shrug:;):D:)
Alex:)

[bojan]

Alex, you are bored, are you ? :shrug:

[xelasnave]

Always Bojan, but Peter raised a hint that he has problems with science so I thought a thread where concerns may be aired, rather than side track the other thread, would be helpful.
I am attempting satire in an effort to have contributors consider their views such that they may wish to distance themselves from the "nutter" who made the OP.
Alex

[glend]

I was watching the SBS program last night on gravity propulsion systems, and the ex-NASA project director was bemoaning that fact that the budget was cancelled to get enough money to build yet another NASA building in some congress-person's state. So my 2 cents, scientific research is hamstrung by politicians vested interest, politicians who don't care about anything other than getting elected again ( and perhaps their NRA endorsement, which seems to be one in the same over there). Their 'future' extends only to the next election.
If we had something like the Future Fund, a Science Future Fund, that politicians could not get their hands on, great strides could be made, and any discoveries that end up making money see the money plowed back into the Science Fund. This would be a great incentive for kids to study STEM subjects, knowing there might be a job in their field.
My 2 cents.

[Somnium]

I predict this thread will be closed in 2 days ... Taking bets

[xelasnave]

May only take just one post. But let all of us act in a way that sees the moderators not having to point out the obvious.
Nevertheless I would hope that if anyone believes a problem exists that we can address the concerns in our usual friendly manner.
I hope everyone understands the word satire and that the OP was my humorous way of kicking things off but feel free to explain the word theory in its scientific context to me if you don't know what satire means.
Alex

[xelasnave]

Hi Glen forgive me not quoting you but I am on my phone and near out of credit.
I don't know where you got the idea politicians only care about getting re elected. A good politician should be able to set himself up for life with just one term in office.
I missed that show the TV gets interference so it was just a pain to try and follow it.
I thought it was probably nonsense but what did you think?
I thought it was about the prospect of anti gravity which I am sure can not work which I will not go into but my words near my avitar may give a hint.
But you raise a good point re funding but how you would prevent even a fund from having problems is beyond me.
Thanks for contributing.
Alex

[Stonius]

plus one million what he said ^^^^^

[sn1987a]

Meh!, it's a waste of time kids today studying STEM subjects.

Computer AIs are already on the job and are getting better exponentially. By the time the kids graduate computer AIs and automation will have already taken their entry level jobs anyway.

The only thing they'll have at the end of it all that STEMing is a massive HECS bill and the dole. Let's just all take it easy, kick back and watch the show!:P

[glend]

Alex, the program reviewed past research projects on gravity propulsion and the reasons they failed to achieve much, such as the M-Drive. It was not nonsense to me, but presented in a non-judgemental way, relying on scientific method and repeatability. The aspect of potential role of anti-gravity, if it can be called that was touched on, in the sense that the universe expansion is actually speeding up - so why, if gravity should be slowing it down and reversing expansion? What is the role of dark energy in the mix? We don't understand the expansion factors well enough yet. If we can find the reason for expansion, it may be a key for controlling gravity. That is what i saw in it, perhaps others saw thing differently.
There are a seemingly endless supply of 'pop' science type documentaries, and i admit i watch most of them, but this one stood up reasonably well on a subject that sometimes is seen as fantasy.

And Barry, are you suggesting we just turn over the world to SkyNet AI now? I still have faith in humans to solve problems in ways AI and their logic based approach just can't. Creativity, visualisation, coming at a problem from a different perspective, humans still do this well.

[xelasnave]

I had to laugh.AI is replacing lawyers.
The only job that will be safe is that of the humble plumber.Their maths is poor, I had one the other day, cause I am sure he had the decimal point a bit to far to the right on his bill.
But what will humans do in the future, besides the plumbers, what work will be available, will we need to work, I was born too early it seems.
Alex

[xelasnave]

Hi Glen
I had contented myself that I was not missing anything but it seems not.
I know folk think I am a crackpot when I suggest this but "they" have gravity a bit wrong in my view. Firstly the force of attraction does not exist we just wrote it in with no more than a belief such a force could work. I say it can not and if you try I doubt you can come up with a mechanism.
However if you see gravity as a flow of energy from all over the Universe, as do I, little issues like dark matter and dark energy disappear.
Now don't get me wrong GR I accept as our current model and it takes care of the math, something I can not do, but I have always thought GR sort to describe the flow of space that I suggest and maybe if tuned a little dark matter and dark energy would not come from the equations.
My only frustration is I spent years developing my idea only to find that Le Sage developed the idea in 1745. The idea is referred to as "push gravity" and looked down upon and jumped upon by GR advocates. However if things "work" along the lines I suggest for gravity it would be unlikely to have "anti gravity" .
If things work as I suggest it is easy to expect the outer stars in a galaxy will rotate faster because the force is external to the system, of course the universe should expand if all this energy is pushing, and as to dark matter if the force is external that may go a long way to explaining why the galaxies don't fly apart.
But they are my ideas and I don't expect others to see it my way and don't get upset the world does not agree so I would like to think I am different from your crank type.
Just a belief.
Alex

[Stonius]

But isn't that the problem right there? The death of the 'expert'? "My opinion is just as good as your science?".



Are you for real here? It's hard to tell?

[Atmos]

I don't think that science has lost its way although from the OP I can understand what you mean Alex. The way that science is conducted has changed as has what is morally allowed in this day and age :P

The way that I like to think about it is that theoretical physicists are here to come up with various ideas to explain various things that we see. While astronomers are here to prove/disprove those theories, some as outlandish as they are!

I do also agree with Glen that politicians these days don't look far enough ahead, they don't look further than 3-4 years (their electoral term) which makes all of their policies about getting voted in again and not so much about what is best for the future of the country.

Just look at our current government, a few years ago we were in the midst of a budget emergency, now we're in a "budget what?" The reason being that fixing the budget before we lose our AAA rating will make people unhappy.

Moving away from politics :P Science isn't what it used to be, a lot of it has moved away from what the "ordinary" person can do because, for the most part, the "next big thing" requires billion dollar budgets. Try all we might, no one us will ever be able to detect one of the first stars to have existed, the Earth's atmosphere doesn't allow it (this is what JWST is for). None of us will be able to build a working cold fusion reactor because it is just too bloody dangerous!

As time moves on, new discoveries move further away from the general population because we need bigger, better and faster things to push the boundaries of what has already been done. We can come up with theories and mathematical proofs but we cannot test them, that is left to the professionals with the bigger, better and faster instruments.

[xelasnave]

So my attempt at satire is lost upon you. But I can understand.
I actually think degrees are a good thing and for the record, although one should never eliminate any possibility,say that UFOs are simply objects we can't identify that seem to be flying but I doubt if they contain aliens.
Certainly we need not devote any time or effort to the mstter , I was being silly.
Alex

[xelasnave]

Hi Colin, thanks for contributing.
I am starting to think my humour is not working.
The idea was that I present like a nut job and I guess I can do that just too well. Oh well...
Anyways let's proceed on the basis I am a wacko and you can practice for the day you encounter a real one.
Alex

[Atmos]

Don't worry, I got your satire :P

[glend]

Whatever you are Alex, I admire that you raise these sort of questions. One man's wacko is another man's genius. ;)

[Stonius]

Ugh! Sorry, I tend to take people literally unless I see emoticons! :-)

[xelasnave]

Not your fault. But smiley faces would have it sortted. I may edit and put some in but my reputation is probably mud by now..
I thought Peter could present his views but talking to him in the other thread he does not seem interested.
Alex

[sn1987a]

[QUOTE
And Barry, are you suggesting we just turn over the world to SkyNet AI now? I still have faith in humans to solve problems in ways AI and their logic based approach just can't. Creativity, visualisation, coming at a problem from a different perspective, humans still do this well.[/QUOTE]



I'm saying that capital will turn the world over to Skynet, you and I won't have any say in the matter. Creativity?, visualisation? Puh! there'll be an app for that. :P

[Stonius]

Sounds interesting, though I don't know enough to have a go at falsifying it. Does the prediction and ultimate discovery of the Higgs Boson poke a hole in it? Maybe we should start a separate thread for the good-natured discussion of all our crackpot hypotheses, I'm sure most of us have them.

[Talby]

I agree with you somewhat Alex. As our knowledge base has progressed ,we take smaller steps as Colin points out. The testing of these smaller steps taking more $ input ,eg the LHC , larger more expensive scopes.(Unfortunately the money controlling research is largely controlled by non scientists and trying to direct that funding to your project has lead to the publish or perish mantra of modern science as a method of gaining that funding :(

[Eratosthenes]

total Knowledge may have vastly increased but human intelligence has remained relatively unchanged for many thousands of years. revolutionary paradigm shifts, as the name suggests, don't come in nice small baby steps (although small steps are needed along the way).

The timing of these paradigm upheavals in science are essentially unpredictable.

Remember ladies and gentlemen a cure for the common cold still eludes Human endeavours. Science has still not provided a full explanation of why a bicycle is stable during motion.

...Collectively as humans we are dumb as door knobs - there is a lot of work to do

[xelasnave]

I do not understand the standard model as well as I once thought I did but that is to be expected I am not a professional but I dont think the higgs accounted for the mass most of us thought it did, and all that tells me is I only read the hype on astronomy daily and the like.
I dont know how you could establish what I suggest particularly having to get those who are so very, understandably, very happy with GR.
Frankly I recon that GR should not need dark matter nor should dark energy be a mystery.
GR is a classical theory it does not need to know why matter can tell space how to bend. All I suggest is really a mechanical type pressure but diehard GR supporters dont need it and they dont, I just think that it would make more sence that something needs adjustment in our math than to believe, what 80 or 90% is stuff we cant see or explain.
I mean I would be thinking maybe just maybe our sums are leading us down the wrong road.
But how do I know one would think the professionals have very good reason to believe dark matter is real. And well if its not real in time they must figure it out.
But as to we each could share ourcrack pot ideas I suggest that usually does not end well, could be worse than discussing religion or politics.
The thing I learnt from my gra ity trip was it does not matter what I think in so far as I dont have to convince anyone. I can imagine it whatever way I like with no neex to convince others I have something they need to know. I have been there however a d happy to step backbefore I lost it.. became a crank etc.
Alex

[xelasnave]

Sorry Peter I was still typing and only now saw your post.
Thank you for joining in and thank you for being a gentleman.
I nearly got in a hole I could not get out of to get this thread started.
People started to think I was half crazy, well I may be but that is the sort of thing I like to keep a secret.
Thank you sincerely for your nice post.
Alex

[xelasnave]

The bike stays upright because gravity works like I suggested. The bike is the system with gravity working as an external force.
I could cure the common cold but I have substantial interests in various paper tissue companies.
Just kidding about the bike.
Alex

[Stonius]

I've always felt very uncomfortable with the idea of dark energy/matter. It feels a little too close to the method Theists use, interposing a preferred mechanism for things they don't understand, and then looking for the evidence that would support their beliefs (very unscientific, IMO, but what do I know?).

Okay, so the expansion of the universe is accelerating, and galaxies rotate faster than they should. Nothing wrong with saying 'We don't know why, and it could be caused by a number of factors'. But calling it dark matter/energy seems predicated on an expected result and seems particularly narrow. I'll stick my neck out and say that I don't think they'll ever find an exotic form of dark matter or energy. Far more likely that they'll discover new physics that explains it, much like a certain patent clerk did a while back.

[ZeroID]

In Steam Punk terms, it's called the Aether, that mysterious medium that connects and influences us all. Now where did I park my dirigible ? :P

And Alex: Don't ever give up your nefarious postings of the weird and wonderful that pushes us all to friendly debate and discussion. Your satire and off beat threads are always both entertaining and informative.

[bojan]

Colin, I agree with most of that..
However, I would like to add one more detail.. about education (or lack of it).
I am coming from times and places where and when the education was considered the ultimate basis for the future of the society.
However, today, I can see (from my angle) that education is actually business - and service available to mainly those who can afford it.
Or just a chip in polititical games our politicians sometimes play.
So I am not surprised that scince and scientists are (by some) looked upon as some sort of closed "lodge", secret business or religion with their priests, who are the only ones to control the explanations to general public.
Many times I had to defend the science and scientists from attacs like those.. and sometimes I also think that the future of human society may turn out to be similar to what was described in movie "Idiocracy".

[bojan]

Well, this is a method - you have phenomenon, you try to explain it the way you can (for now).... you name the explanation in somewhat colloquial language (“dark matter” – nothing wrong with that (or any other) name IMO per se – it only reflects the behaviour (can’t see it)).
For example, I still can’t comprehend why gauge theories are called “gauge”, but I understand (or at least I hope so) what the theories are about. You just have to be member of gang to speak their lingo properly :P

[Dave2042]

You're bang on here and your last post in my opinion.

The main problem here is not that Science (and we're really just talking Physics here) has lost its way. It is that we have been so successful over the past 400 years that the remaining blanks are very difficult to fill in.

First, we only see things we can't explain under extreme circumstances that are very hard to create for testing purposes (LHC energies, inside a black hole, first nanosecond of the universe).

Second, the wiggle-room afforded by what we already know is very narrow in theoretical terms. Any theoretical explanation for the gaps must reduce under less extreme conditions to QM, GR and SM (or something mathematically equivalent), since we already know these give the right results. This is a very tight restriction on 'theories of everything', and one of the main reasons string theory persists as a candidate.

Thirdly, QM, GR and SM are based on some fairly heavy-duty maths, and so any attempt to extend them is also going to be mathematically heavy-duty. If you are not on top of all that maths, you are really just blundering around blindly. (To be clear, I'm only claiming a limited understanding of this myself.)

Finally, while everyone is entitled to express an opinion, some (ahem) opinions on this topic are clearly just the peanut gallery sounding off about something they have no real understanding of and no intention of doing the work to develop an understanding. By which I don't mean normal questions, suggestions and observations that make forums like this fun, more the disparaging of science with nothing of substance backing it.

[sjastro]

To understand the term gauge one needs to know about the mathematical concept of invariance and how this is applied to physics.
A simple example is rotating a triangle in Euclidean space.
The sum of the angles of the triangle will always equal 180 degrees irrespective of the rotation of the triangle in space.
In mathematical parlance the sum of the angles is invariant under a mathematical transformation involving rotation.
A gauge transformation is where invariance is preserved under that transformation.
The term gauge restricts the number of transformations possible.
For example in "uneven" (non isotropic) non Euclidean space the above example is clearly not a gauge transformation as the angles will always change as the triangle is rotated.

The idea can be extended to physics using classical electrodynamics as formulated by Maxwell.
The electromagnetic field can be expressed in terms of vector potentials.
It is found by applying a mathematical rotation results in a gauge transformation as the vector potentials remain invariant.

The obvious question is "so what?".
In the early 20th century before the advent of QM and at the dawn of GR it was found that electromagnetic and gravitational fields when described by a dynamical property known as a Lagrangian would generate the various conservation laws of physics under specific gauge transformations.

Modern day physics is built around this discovery.

The gauge bosons such as photons take the concept of gauge transformations further.
Not only must gauge transformations apply globally but to every individual point in space time.
These local gauge transformations result in the existence of massless bosons such as photons.

[Stonius]

Very clear and lucid. I agree absolutely.



True - what is IIS if not a peanut gallery? It's posts may be reviewed by peers, but it's not peer reviewed :lol:



True, you have to hypothesise something in order to move forward. But I think the name of the effect (literally 'something we can't see) has been confused with the cause; 'an exotic type of matter'. Yet it seems a foregone conclusion that we are looking for dark matter/energy, rather than an explanation of the matter/energy discrepancy (a better name, in my opinion) where the answer could, in fact, have many explanations. I mean, they could have called it 'dark unicorns' for all I care, as long as they didn't actually expect to find space unicorns orbiting the galaxy!

[Dave2042]

Yes, and I like it that way. But it can get a bit tiresome when people push the envelope for what appears to be little reason other than to be confrontational.

[Dave2042]

And another thing (in cranky old man voice).

If you think science has it all wrong, how do you explain technology, which is simply science that's sufficiently well understood that it's been handed over to the engineers?

Put simply, how do you think your fridge works? Or airplanes? Or medicine? Or computers? If QM/GR/SM are all just made up nonsense, then do all these things work off magic?

[xelasnave]

Clearly science is doing a wonderful job.
Why humans who will tolerate so many imperfections in their personal behaviour and yet demand God like performance from scientists and the institution we call "science" is something I have always thought strange, but not to offer a proposal for a better way to do things is stranger still.
In another place someone pointed out the long journey that a scientist must take will see him maybe never being able to discover something grand but its not everyones destiny to discover something new. The expectation that a scientist will discover something new is not certain but what is certain is that a layman or "armchair scientist" will never come up with something that will change anything.
It is one thing to chat about gravity and dark matter, whatever, but quiet another to think anything we chat about here will become the next big thing.
And really there is little I would critisize about where science is today and I certainly can not offer a better way to do things.
The true genius will not be sidelined by the system as many would suggest otherwise nothing would be done and if we look at what is getting done, which takes regular daily effort simply to have a hint of developement, who could say our system is suspect.

Alex

[AstralTraveller]

I don't know about science losing its way but scientists certainly do. The title of the OP reminds me of a story I heard years ago about a quite gung-ho geologist who was driving a car and trailer north through the SA outback. Rounding a corner too fast he spun out. He didn't hit anything (nothing to hit??) and came to rest facing south. Yep, you guessed it; he stuck the car in first gear and drove off. He eventually realised his mistake but, the way I was told, not very soon.

[bojan]

Steven,
thank you!
I guess this issue of mine with term "gauge" has also something to do with the fact that my "mother tongue" is not English.. :thanx:

[AndrewJ]

I liken it to the "age of the priests" in Asimovs "foundation" trilogy.
Once "science/engineering" has given people a good safe living, ( ie cover, water, electricity, food, sewerage ) the scientists/engineers are no longer "perceived" to be needed as much and get relegated down the food chain.
The only science i currently see most people are still interested in is medicine ( and cancer mainly ), as that might still affect them.

Andrew

[redbeard]

As long as they keep sending spacecraft into space and can still contact and manoeuvre them years later then no, science has not lost its way. We are now in a world where business and corporates set the standards but I still see plenty of good science on track. Science is pretty diverse and the corporates don't have it all.....Yet!

[xelasnave]

Well we seem to all agree science has not lost its way but do we know where we are going.
What direction should we be going, should the goal be better life for all, better toys, faster cars, better beer.
As a species should we be thinking what can we do to make sure we survive the planet.
Certainly we don't know what we don't know so is there anyone working out what we don't know.
But what do we do next?
Is it to early to make plans for leaving.If our population keeps growing should we be getting rid of species that compete for our food.
Should we move underground to combat rising temps.
What next?
Alex

[glend]

Given that the human race is responsible for all of the problems facing earth: climate change, warfare, religion, resource hording, nationalism, etc i don't trust humans to fix anything for the benefit of all. Chaos Theory has a better chance of creating solutions.
If we did somehow develop the capability to send people to other star systems to colonise, you can bet the tribes of the Amazon, the Inuit, etc will never make the jump, cultures are expendible. The people controling the budgets will get to choose. Just as in any large corporate organisation, the closer you are to the central tower of power structure the easier it is to get ahead. I think one of my favourite movies captures it very well: Gattaca.

[xelasnave]

I often think of designing a space ship large enough to house ten billion humans and fit the animals, oceans and forrests we want to keep.
As an exercise, you know just to get one thinking.
I try these things as a way of "counting sheep" so I have not even done any sketches.
Probably one quater of the Earths surface as a ruff figure and fit that by layering up so we get an approx volume, then work out approx mass so we can work out approx energy to move it etc. Then work out time to build etc.
I usually design and build just a house and make a list of materials, down to number of nails, lenghts of electrical wire, paint if put on at a thinkness of x.
I find the strain of remembering all that stuff causes my brain to shut down so I drop off.
But the space ship is so big I dont get past the volume I would be happy with.
And I cant remember what I last set upon so I have to always start from scratch.
So as you can see I am just like anyone who has trouble getting to go to sleep.
Alex

[glend]

But Alex how would you power that big Arc type ship? In the program early this week on Gravity Propulsion, the NASA project director gave an example of just how much fuel traditional, present day rocket systems would need to propel a deep space ship to even one tenth light speed, he said you would need the equivalent weight of our Sun in fuel to do that, and of course the ship has to carry it. So using present technology it is not achievable. However, thinking outside the box is discouraged.

[xelasnave]

Well you drop toward the Sun and pick up speed as you pass by you gather all the energy you can (this is a field in itself how to store heat, magnetism anything really) loop by and out when it starts to slow use all that energy plus whatever we have developed to get away from the solar system influence and headed to the next star.
Plus the ten billion humans can blow down a pipe pointing away from where we are going.
Thats the beauty of such a crazy idea you start thinking strang way to achieve the goal.
Not saying anything could work but when you get to brainstorming great ideas often pop out.

And if we have such a craft we really dont have to go far wecould generate power from eliptical orbits.
Working out all the details will take a couple of more nights.
Alex

[xelasnave]

Actually we cant blow down a pipe as we cant lose anything waste air etc must be kept.
Alex

[alpal]

Dear Alex -

we are already on a space ship - it's called Earth.

[N1]

Alex, we will not survive the planet as a species, and there is nothing we can do about it. Homo sapiens sapiens will cease to exist long before Earth does, regardless of where else it might set up colonies successfully and regardless of how well it treats our planet's surface and atmosphere. It will go before Earth, either by destruction or evolution.

Re (space) science today - it's doing just fine, although priorities may need revised. Too much effort goes into on putting people on other worlds as compared to things like impactor detection and deflection. :shrug:

[sjastro]

Bojan,

I'm glad you found something useful came out of this thread, instead of the protestations from the peanut gallery as Dave2042 eloquently stated.

While there is one particular individual at IIS who has let us say has an "unusual attitude" towards scientists, it is comparatively mild to the vitriol served up by anti intellectuals at other sites.
I have been in private contact with one astrophysicist who has explored the idea of legal action against both the individual and the hosting website for defamation.

Unfortunately what this individual has had to put up with (I prefer to keep him anonymous at this stage) is a reflection of what is happening in the US.

https://www.sott.net/article/313177-The-cult-of-ignorance-in-the-United-States-Anti-intellectualism-and-the-dumbing-down-of-America

I suspect the same attitudes prevail here.

[xelasnave]

Steven within the alarming statistics in your link above I found the following.

"Gallup released a poll indicating 42 percent of Americans still believe God created human beings in their present form less than 10,000 years ago;"

As Adam Savage of Myth Busters fame would say "Well there's your problem".

I have experienced continual attacks from cranks at another site for no other reason than I point out the futility of a non professional trying to re write current established models.

I had a certain sympathy for them given where I started, which thanks to you more than anyone helped me start to understand my ignorance of current models etc, was from the position of a complete crackpot, however they are not the same as I was.

Maybe my memory deceives me but I thought I was calm polite and thankful for help.

They are bullies, they have no interest in learning, when they are pointed in the right direction they claim mainstream is nonsence.
They are so quick to get angry, very angry, and instead of trying to have a polite discussion resort to personal attack.
The threads degenerate into mud slinging which I first avoided, but when I started to throw mud back (which I believe I am good at doing much better than them) they report me for being off topic. So the result is there is no point in getting involved.

One chap is ranting about GWs and how they are wrong, whatever his arguement is not easy to follow, but when a real scientist, foolish to get involved really, points out the lack of arguement, lack of equations etc this crank rips into him rather thank him for trying to help.

The only reason I bother with the site is because there is a layman there who posts very good links to mainstream papers and articles and from those I get some interesting and worthwhile information.
But the cranks obviously drive away folk who could contribute but can see they will be attacked if they hint they support anything mainstream.

The site does what it can to elevate the science but these cranks pull it down.
I often think they tolerate the cranks because the fighting generates high traffic.
One chat who is outrageous gets short bans which would bring a permanent ban at somewhere like Cosmoquest. And when he is banned another crank almost identical in expression and views appears.

But as I said I get a steady supply of interesting links so its useful.

What surprises me is some folk there sound inteligent but believe the craziest of ideas, ufo, afterlife etc.

And I hope my satire was not lost on you and you understand why I started the thread.

And its seems Peter was able to realise he could post his views without ripping into scientists.

And for the record I think our science has not lost its way and I appreciate that there are dedicated a d clever humans who devote so much of their life to gaining an education to give their lives to extending humanities knowledge.
Sorry for the sin of starting sentences with "and" and "but" and other wrongs I ignore or have forgotten.
Alex

[xelasnave]

Mirko
You are of course correct.
But my idea was never about reality it was about getting to sleep.
We humans of course think we are it a d will be around for every.
The uneducated, with only one book on cosmology think that, and even the well educated lean that way.
Its seems that evolution is the rule, it is not, extinction is the rule and evolution is the exception.
The giant lizards had a great run but we know what stopped them, and we know it but will we try to prevent the same fate?
Could we prevent a similar fate?
Moving back to the caves is our best hope.
Alex

[xelasnave]

Yes and how we take it for granted.
By saying that I realised the bigest problem in my craft.
Gravity just think of the energy we would need to take care of the problem.
I read that astronauts suffer eye problems cause of pressure on their eyes because of weightless conditions.
No doubt there would be many problems when we move in.
So how to fix that problem.
Artificial gravity or engineer humans for a non gravity environment.
Alex

[Eratosthenes]

Apparently some scientists surveyed have a list of problems in science that they wish should be attended to.

We recently asked scientists a simple question (http://www.vox.com/2016/7/14/12016710/science-challeges-research-funding-peer-review-process): If you could change one thing about how science works today, what would it be and why?
We heard back from 270 scientists around the world, including graduate students, senior professors, laboratory heads, and Fields Medalists (https://en.wikipedia.org/wiki/Fields_Medal). And they told us that in a variety of ways, they feel their careers are being hijacked by perverse incentives.

The top 7 responses are given here

http://www.vox.com/2016/7/14/12120746/science-challenges-fixes

(although most are true about the profession of science, IMO there are underlying causal and structural problems that need to be addressed)

:D

[xelasnave]

Only 270.
I suggest that is a very small sample of the total number of scientists in the world and given they have time to answer a "survey" could that be suggesting they may be twiddling their thumbs and perhaps indicative of under employement or employement with little or no job satisfaction such that their collective moods are somewhat negative and may not represent the scientists who are too busy to take time out to complete a survey because these unsurveyed scientists are engaged in projects very demanding of their time or that they are enjoying high job satisfaction and would not commit time to a survey which they would rather use enjoying other pursuits with their family or friends.

Alex

[xelasnave]

And what about this....
http://www.vox.com/2015/8/27/9216383/irreproducibility-research

Alex

[Eratosthenes]

Alex, yes always need to watch surveys - questions can be loaded and as you say the sample can be skewed or have a bias in it.

A friend works in academia and his department often gets corporate requests to survey products. Most of the advertisements claiming superior washing powder for example are based upon survey results and he has told me that the sample is tiny and they will repeat survey until they get the results their paying clients want to see. then thy claim "University results" or "independent Laboratory" results show this or that.

Its unethical but because the results are not required for peer review publication, they can do whatever they want.

So that washing powder cleaning brightness isnt based upon some fancy laboratory analytical instrument that measures brightness, but rather asking a group of 10 or 20 people what they think of the bed sheets and towels.

So 270 scientists from various disciplines and professional levels is probably a big sample compared to these "independent" academic surveys of corporate products and services.

(Political surveys are the worse for this sort of bias survey because they are deliberately used in the media as spin. 78% of Australians think we should be tough on refugees for example. You can participants "do you think we should help genuine refugees when they seek asylum in Australia?" and get one result or you can ask "Do you think boat people should be treated like all other asylum seekers and go through the normal channels in a fair and orderly manner" and get another result. Its PR spin industry)

:D

[xelasnave]

Has anyone thought to conduct a survey to determine what percentage of the population have completed a survey?
I heard "they" are doing a survey of 1.2 million galaxies to map dark energy.
Is that a fair sample given the massive number out there.
Sounds a lot but it's not.
Alex

[glend]

Ha ha Alex, who are "they" and just who in those 1.2 milltion galaxies are going to fill in the Survey form? I assume it will have to be an online form as Aus Post deliveries might be a tad slow. Even online its going to take a long time to get them back. :lol:

[xelasnave]

I knew something sounded fishy but I just could not put my finger on it.
By the time all the forms are in everyone of those galaxies will have moved.
We will need another survey to work out where they moved to.
When I read about the proposed research I thought, as most people probably would, wow that is a lot but really when you think how many are out there a mere million is such a small percentage.
Think of the Hubble deep sky shots, a gain of sand at arms length hides thousands and that result would go for wherever you tried that move.
I wonder if the researcher gets paid for each galaxy. How much time would you give to each galaxy.
You would have to write its name or number, a location, where it is going, speed, mass, luminosity.
Heck you would want at least $50 for each one.
So I wonder how much the grant was?
Is there a survey on how many people make their living from doing surveys.
Are surveys science?
Will it ever stop raining?
Alex

[glend]

I would be happy to count them and fill in a form if they are going to pay me. Plenty of retired people would not mind the work. They just need to send me a file. I used to process SETI data blocks on my home PC, worked in idle time, a SETI app would run all the tests on the latest data block and then send SETI a report on any abnormalities in that block for further investigation, and then i would get sent the next data block. My son ran it as well on his PC.
If they distribute the galaxy survey in that way it would not take too long.

[xelasnave]

The more I think about it the more I wonder how only 1million galaxies would indicate much at all.
I wonder how they would go about getting anything using so few.
Alex

[Stonius]

It's early days, but this looks promising;

"A new theory of gravity might explain the curious motions of stars in galaxies. Emergent gravity, as the new theory is called, predicts the exact same deviation of motions that is usually explained by invoking dark matter. Prof. Erik Verlinde, renowned expert in string theory at the University of Amsterdam and the Delta Institute for Theoretical Physics, published a new research paper today in which he expands his groundbreaking views on the nature of gravity.

According to Verlinde, gravity is not a fundamental force of nature, but an emergent phenomenon. In the same way that temperature arises from the movement of microscopic particles, gravity emerges from the changes of fundamental bits of information, stored in the very structure of spacetime."

http://phys.org/news/2016-11-theory-gravity-dark.html

Actual paper here;
https://arxiv.org/abs/1611.02269

Markus

[xelasnave]

Hi Markus
I don't like the chances of getting rid of dark matter it is now a business with many depending upon research about it and researching it enables us to use old mines that otherwise would have no other use.

An ignorant chap like myself would wonder why upon observing that rotation curves did not match the model rather than look for invisible matter rather it would seem to me that an adjustment of the model would have been appropriate.
I bet the stuff you bring gets buried.
Alex

[bojan]

Verlinde's paper from 2010
"On the Origin of Gravity and the Laws of Newton" (https://arxiv.org/pdf/1001.0785)

[sjastro]

Frankly I've lost count of the number of papers I've read over the years where dark matter can be dispensed with by modifying gravity, using GR models, holographic model etc.

Despite the issues in detecting dark matter, the phenomenological evidence is considerable.
It's interesting to draw parallels with the dark matter problem of the mid nineteen century called Neptune. The irregularities in the orbit of Uranus led some scientists to suggest that Newtonian gravity needed to be modified.

The discovery of Neptune based on the calculations of the orbital perturbations in the orbit of Uranus was a major triumph for Newtonian gravitational theory.

[xelasnave]

I am up to page 5 and have a feeling I am wasting my time.
Have you posted this to prove he is a great scientist or a crank.
It may be that I dont appreciate something but I would appreciate your opinion before I read any more or if indeed I should read more.

Alex

[Stonius]

And me! But according to Bojan, this is not a new train of thought, so I assume it must have been discarded for [reasons].

Will sit down to read that paper when I have a minute, but at first glance, it looks like the hypotheses are similar. There's nothing new under the sun!

Cheers

Markus

[sjastro]

I read this paper which seemed suspiciously familiar until it dawned on me it was discussed over a year ago in the science forum.
The concept of gravity as an entropic force has compatibility issues with basic quantum mechanics and would contradict what is observed in the double slit experiment (https://en.wikipedia.org/wiki/Double-slit_experiment).

Here are some of the comments made.

[xelasnave]

Thanks Steven I must confess I did not recall it.
And excellent point re Neptune.
Alex

[bojan]

Author is also the same ;)

I posted this link to remind you guys (and me) that we discussed this earlier, but I forgot exactly when was it.
Steven's explanation nailed it right through.

[Stonius]

Apologies for going over old ground. I think this must have been just before I came along :-)

-Markus

[sjastro]

No need for apologies.
It's popped up on Brian Koberlein's site.
https://briankoberlein.com/2016/11/14/emergence-of-gravity/

Incidentally Brian Koberlein is a real character and a very good science communicator.
Unfortunately some of his pupils have rather different opinions.:(
http://www.ratemyprofessors.com/ShowRatings.jsp?tid=348120

If only this rating system was available when I was at Uni..........:P

[madbadgalaxyman]

Agreed!!!

I once asked a leading Dark Matter theorist , "do you really (and truly) believe in Dark matter?"

He replied that "you have to go where the data leads", as all the existing data on the space velocities of the galaxies (and their member stars) can be currently explained simply by positing the existence of large amounts of some kind of unknown gravitating matter, whether in the form of exotic particles, dust, stars, low-albedo copies of the Astrophysical Journal, or something even stranger.

There is currently no necessity for any other explanation of the kinematics and dynamics of the galaxies and their constituent stars, as so far observed by astronomers.

However, of course, the reason for the observed velocity field of the galaxies and the observed velocities of the stars within them, could be some other strange thing, so there is nothing to stop scientifically informed speculation as to some other cause.

The dark matter problem was already well known to Fritz Zwicky in the 1930s, as he had measured the velocities of the galaxies within large clusters of galaxies, and he had found that the orbital speeds of the galaxies were so high..... that several times the observed amount of visible (luminous) matter was required to keep the cluster of galaxies stable (to stop the galaxy cluster from flying apart)

Tiny dwarf galaxies have the same problem, in that much much much more matter is required to hold them together than is observed. In particular, the faintest dwarf galaxies have very-widely spaced stars, and very few stars in them. The observed amount of luminous matter in these tiny dwarf galaxies is ridiculously small, yet they do hold together;
at the extremes, two or three hundred times the observed amount of matter is required to hold together an ultra-low-luminosity dwarf galaxy!

Obviously, the existence of a galaxy which looks like a powder-puff, but which seems to be dominated by large densities and amounts of dark matter , does cause some astronomers to wonder if that vast amount of additional "dark" matter is really there?

So I think it is natural to wonder, given that dwarf galaxies exist where the gravitational field requires one or two hundred times the observed amount of matter, whether all of that additional matter is really there. But this sort of thinking comes under the heading of "interesting speculations"
___________________________________ _____________


And you guys (not sjastro...) , stop lumping dark energy and dark matter together.
(so I suggest that you get educated(!!) as to exactly how stars and galaxies do move, and you will see the difference. The observed line-of-sight velocities of stars and galaxies, and increasingly, their transverse velocities "across the observed sky", constitute a vast existing set of observations and data , all of which can be explained perfectly-well by the dark matter hypothesis and standard gravity. However, astronomers still do look for other explanations for the velocities of galaxies, such as "large scale cosmic flows")

Dark matter is very-well-established and nearly universally assumed to exist by all professional astronomers!!
(science, unlike theology, does not deal in certainty, so when astronomers become perhaps 70 percent certain that black holes exist and 70 percent certain that dark matter exists, they allow themselves to talk of these things as if they really do exist)


In contrast to the status of Dark Matter, Dark Energy is at the frontier of what can currently be observed and understood.

__________________________

There are currently a number of surveys, in progress and in planning, of very large numbers of galaxy redshifts (line-of-sight velocities of galaxies) that are designed to look for exotic effects such as dark energy and "boojums"(= unknown effects), but this should not detract from the fact that the velocities of things in space are pretty much universally explainable by standard gravitational theory.
___________________________

[xelasnave]

Hi Robert
Firstly thank you for your post I found it very interesting.
I was under the impression that dark matter was a form of matter which in effect we are unaware of its nature, further that it is something exotic and not normal matter.
Your post hints that it may be dust or stars even journals that dont throw light on anything are we to take this to mean that some exotic particle is but one option and somewhat normal matter may be there but we simply can not detect it.
I have the impression that dust stars or journals would be detectable by means other than gravitational influence. Are we to take it that this dark matter may indeed be normal matter, for example dust issolated planets er rocks without a sun and that the prospect of a new particle is but one of the prospects for dark matter.

Your comments re dwarf galaxies surprised me as to the amount of dark matter required.
Two to three hundred times more dark matter required I find extraordinary.
I have heard numbers which suggest a great deal more dark matter than ordinary matter but two to three hundred times more in a specific situation makes me think back to my original concern that our sums are wrong.
It seems inconceivable (of course anything outside human experience can be inconceivable) that in the case of our dwarf galaxy finding we observe one two hundreth or one three hundreth of the matter really should suggest we seek a review of our current science on gravity.
You are lucky in that you have not heard me rattle on about gravity in effect working like a pressure system, that is force acting from the outside in not in a fashion we term attraction, but if gra ity acted as a form akin to external pressure I doubt if we would need such enormous amounts of dark matter if indeed we need any.
Unfortunately I cant take it further with any theory or even drag together enough to lable my tboughts as a hypothisis.
I just think unless you can say our dark matter may be dust rock or some normal matter to search for new matter just seems somehow more an effort to resist altering our math and our theory of gravity.
The huge amount of dark matter required in the case of a dwarf galaxy scfeams to me that we need to investigate alternative gravity theories... Even the somewhat discredited theories that hint of no dark matter.

I suffer from no education in this matter and look to you (and always Steven) for help.
I am not a nutter orcrank in that I really do try to understand and accept mainstream position.
Alex

[madbadgalaxyman]

Hi Alex,

Well, all we have to go on is the observations of the velocities of galaxies and stars and other astronomical objects. In fact, mainly, with the spectrograph attached to our telescope, we can find only the 'radial' (in the observer's line-of-sight) velocities of astronomical objects.
Subject to various assumptions, we can convert these radial velocities of objects into approximate (statistically correct)(averaged) knowledge about the orbits and velocities of astronomical objects in three-dimensional space.

The most parsimonious assumption, without introducing unnecessary and additional hypotheses (= Occam's razor), is simply that the observed velocities of galaxies and stars , because they do not correspond to the velocities that we would expect to observe if these objects were just under the influence of the matter we can observe by means of its emission of electromagnetic radiation (light, X-rays, infrared, radio waves, etc.), are best explained by the combined influence of gravity that comes from ::
(1) a component of matter which we can easily see from its emission of photons
(2) Another component of matter which is currently not detectable at any wavelength, with the current state-of-the-art Light Gathering Power and sensitivity and noise-level of our telescopes and detectors.



All we know is that there is a lot of additional gravity there that we cannot account for.........the galaxies and the clusters of galaxies would not be stable, and would fly apart, if all that was holding them together was the gravity from the observable stars and gas and other objects.
But of course, the objects that are producing the necessary additional gravity are not known, as we cannot currently detect them with our telescopes and their attached instruments. As mentioned, Zwicky knew about this in the 1930s, from his observations of the orbits of galaxies within clusters of galaxies, but astronomers were not ready to accept this implication until the early 1970s.



Alex, the sums are not wrong, if we assume conventional gravitational theory, and while it seems far-fetched to believe that 299/300 of the mass of a dwarf galaxy is in some unknown form, very simple algebraic calculations of the sort that some of us learn to do in Year 12 Physics Class show that the gravitational effect of this additional matter is there and likely to be real. Which gets back to my original point that there is no reason to believe any other hypothesis about the origin of the velocities of galaxies and their constituent stars.

The case of dark matter may be compared to the case of the theory of evolution........
the story revealed by science seems extraordinary, and perhaps counter-intuitive, but "these are the truths that we must cling to, in the absence of further observations disproving them or modifying them".

As I mentioned before, science cannot provide absolute certainty, and we can only say that it is more likely than not that something is true. So, for now, we must earnestly speak about dark matter as being something real, as that is where the current observations point.



I absolutely respect your open mind, and your strong desire to learn ever more about what is physically real and what is not physically real, in this grand universe of ours.

[xelasnave]

Thank you Robert for taking so much of your time to help me I sincerely appreciate your effort.
Alex

[croweater]

Hi crew, Are the galaxies surrounded by dark matter or actually in clouds of dark matter? Would gravity waves be emitted? Thanks Richard

[julianh72]

Alex,

I'm probably going to sound like I'm advertising for Penguin Books because of the number of my recent posts advocating "Universal: A Guide to the Cosmos" by Brian Cox and Jeff Forshaw https://www.penguin.co.uk/books/180728/universal/ but I'm not, I've just found it to be a superb account of the state of modern cosmology.

It's current (published September 2016), and very readable, being co-authored by two excellent public-outreach scientists. (Brian Cox will be very well known to most of us; Jeff Forshaw less so, but he has worked with Brian Cox before.)

What I really like about the book is that explains and presents the actual data which is being relied upon, outlines the maths which is used to interpret it, and invites the reader to work it out for themselves using the data, graphs and formulae provided. It also explains how data collected from multiple, completely different sources supports the same conclusion - Dark Matter, Dark Energy, and accelerating expansion of the Universe are not simply an artefact of a single set of observations, or an empirical requirement to force a particular theory to match a subset of the data.

Like you, I find it hard to comprehend that we simply can't detect most of the "stuff" that makes up the Universe, and don't even have a solid consistent theoretical basis to understand what that "stuff" is, and yet, that is where the observations take us.

The good news is that this means that "Science isn't dead" - we know that we still have much to learn. I think it must be something similar to the state of Classical Physics at the end of the 19th Century and early 20th Century - there was a feeling that we pretty much understood everything, and all we had to do was dot the Is and cross the Ts - and then along came Einstein, quantum mechanics, etc, and suddenly, we realised that we understood nothing!

[madbadgalaxyman]

There are a lot of small galaxies about which are constantly merging with big galaxies like the Milky Way and M31 and NGC 253, and these tiny dwarf spheroidal galaxies are thought to be dark-matter dominated (as per my recent two posts), so this would argue for a certain amount of lumpiness in the dark matter halo of a big galaxy.

The scientific work on the amount and distribution of dark matter in the halos of galaxies involves using small objects that rotate around a galaxy ( like globular clusters and planetary nebulae) and measuring the component of the velocity of each object that we can observe;
measuring the radial velocity of each object. These orbiting objects are used as "test particles" to try to figure out the distribution and amount of gravitating matter (= "bright"(luminous) matter plus "dark matter") around a galaxy.

Another way is to observe the X-ray emitting gaseous halo of a galaxy or cluster of galaxies and to try to figure out how much mass is needed to stop the gas from escaping the galaxy or galaxy cluster.

You can also use gravitational lensing of the light from a background object behind a massive object like a cluster of galaxies ,in order to try to figure out the amount of gravity and matter that is in the path of the light rays from a more distant object. The gravitational bending of light from background objects is one of the most important pieces of evidence for the existence of large amounts of matter in some form that is currently not detectable in photon emission.

I will have to pass on the question of the structure of dark galaxy halos, as I am not up on the current literature!

[Dave2042]

My two cents' worth.

If the only reason we had to suspect dark matter was galaxy rotation curves, then a fair amount of scepticism would be warranted, in my view, and tweaking gravity would be a very good candidate explanation.

The problem is that there is a whole pile of other independent evidence that there's a whole lot of mass out there that we just can't see. Unfortunately it doesn't get a lot of public airplay, because it's a bit more abstract and I suspect most science journalists simply zone out.

The wikipedia article is a pretty good high-level overview.

https://en.wikipedia.org/wiki/Dark_matter

[sjastro]

Richard in answer to the second part of your question any asymmetrical rotating object or objects rotating around a centre of mass can in theory generate gravitational waves.
It depends on whether dark matter in the halo can form clumps which are dense enough to generate waves.

Even if this was possible there is the caveat that such waves could be beyond the range of detection of any current or planned wave detector.
The LIGO detector for example can only detect gravitational waves in the range of 10 Hz - 10 kHz, which corresponds to the orbital decay of dense objects such as Black Hole pairs around a centre of mass.

[Stonius]

Thanks for taking the time to explain. Obviously a lot of very smart people are looking at this and drawing the same conclusions. Can I please trouble you to help me understand the distinction here?



Isn't that just saying gravity theory is correct, but only if you assume it to be correct in the first place? Why assume it to be correct at all when the data suggests otherwise? That's what I don't get!

On the one hand you have the proposition that the physics is somehow wrong at large scales.

On the other you have the idea that most of the universe is made up of matter that doesn't absorb or emit any form of energy, interacts only through gravity and can't be found despite many years of searching.

Surely at some point occams razor cuts the other way where the simplest explanation is simply that conventional gravity is *not correct. Alex nailed it on the head before. Surely the response to data that doesn't line up with your predictions is to change the model and test that? Sure, Dark matter does represent a revision to the model, but why does it represent our best hope over and above any revision to gravity?



What if the story of dark matter is the same as the story of the Ether? Something made up to make the math work out?
I'm willing to accept things that are not intuitive, with evidence. Quantum field theory in bonkers, but I accept that is how the world is. The evidence in this case may have more than one explanation. Why do we exclude the other one?

Obviously I must be wrong in this because professionals who spend every waking moment of their lives thinking about this stuff all like the dark matter explanation, but I wish I knew why it's more likely than gravity theory needing a tweak. Theories come and go all the time why are we stuck on this one?

To put my devil's advocate hat on for a moment and argue against myself for a moment, I assume that an explanation that tweaked gravity theory would expect the effect to be uniform. You wouldn't have a dwarf galaxy with 300 times the effect, and a normal galaxy with, say 5 times. It would (presumably) consistently be proportional to the amount of observed matter.

*sigh. Now I need a pan-galactic gargle-blaster. :-)

-Markus

[croweater]

Thanks for your replies SJ and Robert. I guess we have no idea whether the DM is rotating? I assume it would have to be? Thanks Richard

[croweater]

Sorry another Question. Are there physical or theoretical limits to the frequency of gravitational waves? Cheers Richard

[xelasnave]

Hi Julian thank you for all your book recommendations.

This is off topic but I must share.
Some may have guessed I am an athiest who follows the teachings of Jesus but does not believe he is/was God nor do I believe in the resurection.
I often chalenge theists. "have you read the bible cover to cover?"
Once I owned a magnificent library however it was taken along with all my possessions by the bush fires in 2002?

I now have only one book to my name is a copy of the king Georges version of the bible.
How I got it I have no idea maybe I found it in the house in the city...

I just think that is so funny particularly because on another forum I often say to cranks (intelligent design folk, no evolution etc anti science religious folk) .....
"You need to read more than one book to understand cosmology" or similar.

You really have to laugh... and I hope you all have a laugh... its free its on me.
Alex

[bojan]

This would be my argumentation in favour of current gravitation theory as well.
Exactly this kind of reasoning suggests that current theories of gravity is correct.
Only we have some excessive but invisible mass which manifests itself by its gravitational attraction.

[xelasnave]

I am convinced there may be something wrong with our understanding of gravity.

Unfortunately with no education it is unreasonable to think I have the answer when so many professionals over centuries have built up the current model.

Some older members will remember when I was obsessed with understanding how gravity works seeking a mechanical explanation.
I spent years thinking about it and came up with the notion that therecould be no force we call attraction. To me I could not entertain a mechanism that seemed to require a two way message system. The result of all my thinking lead me to form an idea (please not I do not use the word theory because I understand a d respect science and scientific method) that gravity could be explained by the flow of particles and or energy acting as a pushing force.

I really thought I was going to help humanity with my "unique" idea.
Well the funny thing was a chap named Le Sage came up with the idea in 1745 and it was around in Newtons time and he seemed to have been aquainted with the notion.
I have tried to follow the history and it seems the push gravity idea was certainly around upto the time of GR.

It is said the idea was not taken seriously back in time but frankly I think that has a little to do with installing the new science of GR.

Well at this point most folk who have an idea like mine go crank and anti mainstream but fortunately folk here were kind and helped me, particulary Steven, and extended tolerance I have not noticed such tolerance anywhere else. Steven was very patient and I can never thank him enough for his kind effort as he enabled me to start to understand science how it works what it does and what it does not do.
Thank you again Steven and all the other wonderful members from that time.

I try and work with what I have and I was able to rationalise in my mind that GR did not exclude my idea as to the mechanism.

GR advocates however do not like push gravity and wont have it and you can find folk and lists on the net showing why push gravity is wrong.

Yet GR does not need a force it is a co ordinate system.
I was told I need math and of course that is true but I have little math so given all were happy with GR and it could deliver on predictions I was happy humanity did not need my help. I did predict the pioneer would slow but they have found reasons other than mine but I did think space would slow them and in time stop them. And of course with no math I could not say what time frame..

Nevertheless I did try to do some math.
I first tried to imagine what would pass through a single point in remote space and to make this managable I thought of a sphere ten billion light yeras in diameter with no matter. Thru this point I tried to work out how many trajectories would/could fit.
Sortta like Hershel working out energy from the Sun.. How many points could I fit on the surface of my hypothetical sphere.. Well I did get numbers working on one for each square millimeter but it became apparent that the number of tradjectories were at least geometrically infinite.

So thru our point the tradjectories were vast.

Now what could travel along just one trajectory... particles energy? Well a dam lot what ever it be.. Say just neutrinos to get a mind picture...
Can you see where this is going. It was not an unreasonable conclusion in my view to think simply at one single point there was the potential for a range from nothing to near infinite (I know there is no such number but in this case so large a human could say such a nonsence)
And on this hypothetical sphere we have nothing to contribute to this flow of something other than what galaxies remain on the outside of our sphere .

What percentage of the trajectories carry something I dont know but think of where each tradjectory comes from... Back to cosmic background radiation at least, our sphere really would be our observable universe and that is roughly 90 billion light years dia.

So our one point would have so much passing by I think it offers some hope that space could be looked at as a presure system.

So what difference would a pressure system have from a attraction system.
Well here is my problem I can only suggest that holding things together via attraction which will have a finite power as to a system that has behind it an almost infinite power source to me offers a way of avoiding the need for dark matter.

Also if things work this way one could imagine this way would offer a reason why the universe seems to be expanding as if something was pushing it apart. So we have our dark energy.


Now my belief in GR is such that I believe GR should be able to offer math in support because although I do not understand GR as a professional would I understand it is an attempt to map the flow of space and I believe that GR can only conclude there is no dark matter if it simply maps the flow of space.

Alex

[julianh72]

The simplest way to think of it is to take a look at the observed rotational speeds of stars around galaxies as a function of their orbital radius - which have been measured in the Milky Way, and numerous other galaxies:
https://en.wikipedia.org/wiki/Dark_matter_halo#Rotation_curves_as _evidence_of_a_dark_matter_halo

If the distribution of total matter was proportional to the observable (luminous) matter, the overall density would decline with radius, and we would see the orbital speed fall off as the radius increases - just as we see for planets around the Sun, for example. However, what we actually see is that the orbital velocity is relativity uniform over very large scales.

The simplest explanation is that there is substantial distribution of otherwise unobserved matter throughout the galaxy, not just clumped together with the observable matter. The same argument is logically supported when looking at orbital velocities of stars within numerous galaxies, and the interaction of numerous galaxy clusters etc - but the relative abundance of dark matter varies in different galaxies and galaxy clusters.

The alternative explanation (i.e. that we can see all of the matter that is out there, and it is our theory of gravity that requires correction) would require some very strange re-formulation of gravity.

For example - consider two galaxies with different rotational velocity distributions. Postulating a different distribution of dark matter in the two galaxies would account for these variations, but assuming that the observable matter is all of the matter would require a different Law of Gravity in the two galaxies. Occam's Razor suggests that Dark Matter is the simplest solution - now we just need to work out what it is.

[sjastro]

The attachment answers your question.
Each phenomena produces gravitational waves of a particular frequency range.
The h axis is roughly a strain measurement for how a interferometer type gravitational wave detector should respond to the incident gravitational wave.

Apart from the direct detection by LIGO, an indirect detection of gravitational waves in the extreme low frequency (ELF) range is theoretically possible by a signature polarization pattern of cosmic background radiation photons produced during the inflation stage of the early Universe.
A discovery was announced by the BICEPS project a few years ago but was withdrawn as scientists underestimated the polarization effect from local sources such as magnetized dust in our galaxy.

A major embarrassment for mainstream science but an example of the relentless analysis and verification procedures when "discoveries" are announced.

[sharpiel]

If we could elect our gods you'd get my vote Alex. I love reading your posts. And I think you'd do a great job.

[Eratosthenes]

xelA....this may be an advantage - your mind hasn't been fully contaminated with the Religious Scientific doctrine and fundamentalist scriptural dogma parroted by these laboratory and theoretical Priests carrying these so called "text books" which are commissioned and distributed by the Scientific Jehovahic Churches...

Take String Theory for example - a complete and farcical circus run by deranged ring masters and clown acts

I want to hear more from you xelA about this thing called "gravity"
:D


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(Self-education is, I firmly believe, the only kind of education there is. -Isaac Asimov)

[xelasnave]

Hi Peter
I think you are being un necessarily unkind in your generalised criticism but I dont know enough to try and defend those you attack and can only say you are entitled to your opinions.
It is a little unfair to take a swipe at all these folk given as with most human groupings we can find both good and bad humans.
Often the bad ones give the good ones a bad name and that is why it probably is best if you see something deserving critism you be specific.
I do think as a great deal of what we learn about science comes from journalists and writers of popular books which probably does not present the real picture.
I dont know what the real picture is however I look at things this way.
Science occupies many great minds and even if they produce nothing you feel is worthwhile at least we have manyhumans occupied in work they believe in and as such gives them high self esteem.
Now I would not take high self esteem away from any human for it is a most difficult thing to have a human to accept.

I can tell you much about gravity other than as I said I believe it is a flow of space which could be best described as acting as a pressure system.
I believe there is no force whatsoever we describe as attraction and I think it was something we took for granted and never really thought thru.
And so as simple as it sounds GR probably could do away with dark matter and dark energy. I simply think the irony maybe the maths that give us these hidden features in the universe may well be able to remove the very problem they create.

Alex

[xelasnave]

Les you could make me blush if my feet were not firmly "pushed" to the ground.
Thank you for your kind words of support.
Keep up the good work.
Alex

[croweater]

Thanks Steven , your response much appreciated. Very good of you. Cheers,Richard

[sjastro]

Hello Markus,

Since Robert hasn't responded to this post (yet) let me make some comments.



Scientists are adverse to using terms such as "correct theory", as theory is only as good as the accuracy of the prediction being made when compared to the experiment and/or observation.
The other variable is the sensitivity of experiments.
As technology improves the sensitivity of experiments increases which may show up deficiencies in the theory.
For example for 250 years the moon's orbit was modelled as an object in gravitational free fall as described by Newton.
This model agreed with observations of the time until Apollo astronauts put mirrors on the Moon allowing the Earth Moon distance to be measured with greater accuracy and precision.
It is found the Moon Earth distance is increasing in contradiction to Newton's model and is due to the effect of tidal forces that needed to be factored in with the free fall model.

The data does strongly suggest that dark matter exists as explained below.



The alternatives lead to far greater difficulties than the dark matter model.
The entropic model for gravity has been shown to have serious theoretical problems.
Any model that dispenses with dark matter which also includes gravity modified models cannot satisfactorily explain the presence of gravitational lensing beyond the visible boundaries of colliding galaxy clusters such as the Bullet Cluster. (https://en.wikipedia.org/wiki/Bullet_Cluster)




Ether wasn't made up to make the maths work out.
There is nothing explicit in Maxwell's equations that requires an Ether.
Ether was ruled out by the Michelson-Morley experiment (https://en.wikipedia.org/wiki/Michelson–Morley_experiment) and there was no need to tinker the equations as a result.

The idea that dark matter is made up to make the maths work out is a common misconception.
In a simple solar system involving a star and a single orbiting planet, Kepler's third law is valid. Add another planet to the mix which gravitationally interacts with the existing planet and there is a deviation from Kepler's law.
Newton's theory of gravity being a linear and a perturbative theory (https://en.wikipedia.org/wiki/Perturbation_theory) allows the mass of this planet to be calculated irrespective of whether it is observable or not.
The same principles apply to much more complicated systems such as galaxies in which dark matter is calculated based on deviations from Kepler's third law.

Deviation from Kepler's third law is the observation of the effects of dark matter.
Another misconception is the complete lack of evidence of dark matter itself. While dark matter hasn't been directly observed, we know of the existence of a dark matter "particle"- the neutrino.
While neutrinos alone cannot be the constituent of dark matter, it possesses a very important property which separates it from ordinary matter, a zero charge instead of a neutral charge associated with normal baryonic matter such as neutrons. A zero charge is a fundametal property for the practically non existant interaction with electromagnetic radiation.



If you mean observation to include the deviation from a Keplerian orbit, that's a good reason as well.

Regards

Steven

[Stonius]

Sorry Steven, took me a while to get to this post. Thanks for replying in such detail.



Fair enough :-)



Fascinating read. Is this the case with most gravitational lensing interaction galaxies? That the baryonic (gas) matter interacts in a different way to dark matter? I mean is this galaxy an anomaly, or increasingly seen as typical?




If was a done deal, why did Einstein tinker with Aether 33 years later?



Okay, that would make a lot more sense to me - that Neutrinos are responsible for dark matter. The particle has very little mass, interacts only very weakly, is predicted by the theory, has been detected. Makes sense. Maybe there are just more of them out there than we thought.

Looking at the rotation curves of the galaxies the thing that strikes me is not that the galaxies are rotating faster than they ought to, but that the galactic rotation curves are linear - the outer parts of galaxies seem to orbit the centre of the galaxies at the same rate as the inner parts. Wouldn't this require an inverse distribution of dark matter to make the outer parts speed up in relation to the inner bits? If it was just more matter, the velocities would be high, but not flat, right? Even with dark matter we still have to explain why the outer parts orbit at similar velocities to the central parts, don't we?

Cheers

Markus

[sjastro]

Hello Markus,



I don’t know whether this is an anomaly or even if colliding galaxy numbers are numerous enough to form a decent sized data set for analysis.

One thing that is known however is that the orbital velocity of individual galaxies in clusters exceeds their escape velocity which formed the original postulate for dark matter in the 1930s.
The total mass of galaxy clusters must exceed the mass calculated from visible matter otherwise the clusters would fly apart.



Einstein’s view of aether was very different to the conventional view in the 19th century.
In the 19th century aether was considered to be a medium that allowed electromagnetic waves to propagate through, much like air being a medium for sound waves.
Einstein used the term aether to describe the “physical” properties of space-time in the presence of matter


A problem with claiming that dark matter is composed of neutrinos is the very low neutrino rest mass.
In the early Universe which was much hotter, the neutrino thermal energies would have resulted in a much more even distribution of dark matter.
Instead today dark matter like ordinary matter is concentrated in regions such as galaxies.
One would require a heavier particle in order for gravity to counter the thermal effects in the early Universe.



From your attachment you will notice the orbital velocities increase sharply at low radii. This is due to the high density of visible matter at and near the core.
This region rotates as a “solid” object like a wheel, and the tangential velocity is simply the product of the radius and the angular velocity of the individual stars.

As you increase the radius you are adding more outlying mass to the central region that will affect the tangential velocities of the outer stars.
A flat rotation curve is due to the linear increase in central mass with distance.
This can be shown by using high school physics which also serves to illustrate that dark matter was NOT introduced to get the maths right.

An object of say unit mass rotating about a centre experiences a centripetal force equalling v^2/r where v is the tangential velocity and r the radius.
The corresponding centrifugal force has the same magnitude but acts in the opposite direction and equals –v^2/r.
If there is a mass M at the centre the gravitational force of attraction with the unit mass is GM/r^2.
For the orbit to exist to force of attraction must be counterbalanced by the centrifugal force hence.

GM/r^2 -v^2/r=0
M = rv^2/G

Hence the central mass M increases linearly with distance.

Since part of the rotation curve for our own galaxy falls within the visible region where ordinary matter appears to dominate, the linear dependence of central mass on radius can be confirmed.
Since the curve remains reasonably flat where there is less and less visible matter, there must be unseen matter present for the linear dependence on radius to be preserved.

The obvious question that arises here is why dark matter is not simply dark baryonic mass or in other words unseen ordinary matter.
We see the effects of dark baryonic matter when astronomers observe the centre of galaxy which is obscured by gas and dust.
The centre of the galaxy is opaque to observation in the visible spectrum but more transparent in the IR and longer wavelengths.

Given that no difficulties occur when observing through the dark matter halo, it cannot be unseen ordinary matter but matter with very little or no interaction with light.


Regards

Steven