Looks like some upset string theorists

[Solanum]

http://media.caltech.edu/press_releases/13286

Well a few of them at least. Be very interesting if the advanced LIGO finds nothing...

[renormalised (Carl)]

IMO...too early yet to really say anything. Has it occurred to them that their detector might not be sensitive enough and that's why they haven't found any gravitational waves from the Big Bang. They can only surmise in theory what energy/wavelength/frequency the gravitational waves (hence, gravitons) will be, but that doesn't mean to say that is in fact the case. In actual fact, apart from what Einstein had come up with about gravity in his theories, they really know nothing about it. Much of what they think they know about it is still conjecture...maths on a blackboard. It maybe right, but then again it may not be...even though quite a few observations made over the years tend to support the theory and the maths which underlie it.

Here's a clanger....what if they never find gravitons.

[Solanum]

Well, I know that if I don't get the results I expect the first thing I check is my instrumentation! However, one hopes that on things of this scale they are pretty sure they haven't stuffed up. I think it just rules out a pretty small subset of theories, as it limits the size of gravitational waves.

It would indeed be interesting if the don't find any. It's about time something in the standard model severely didn't work, give the theorists a bit more of a hard time!

[freespace]

Originally Posted by renormalised

IMO...too early yet to really say anything. Has it occurred to them that their detector might not be sensitive enough and that's why they haven't found any gravitational waves from the Big Bang.

The point of the article was to say, given the sensitivity of existing detectors and non-detection, an upper limit of gravity waves, if any, exists.

They are not saying gravity waves don't exist, simply if they do exist in the background, then they can not big larger than X because otherwise their instruments would have detected it.

They can only surmise in theory what energy/wavelength/frequency the gravitational waves (hence, gravitons) will be, but that doesn't mean to say that is in fact the case. In actual fact, apart from what Einstein had come up with about gravity in his theories, they really know nothing about it. Much of what they think they know about it is still conjecture...maths on a blackboard. It maybe right, but then again it may not be...even though quite a few observations made over the years tend to support the theory and the maths which underlie it.

Gravitons comes from the standard model's idea of force as an exchange of mediator particle. It is quite distinct with the idea of gravity waves which stem from a view of gravity as curvature in space-time.

Current detectors are not looking for gravitons, they are looking for gravity waves - ripples in space time. The detection of gravity waves will do nothing, afaik, for gravitons, but will confirm a prediction of general relativity.

Here's a clanger....what if they never find gravitons.

Then we will have to come up with better theories At least now there is something to do

[renormalised (Carl)]

I probably didn't read the article properly anyway...being late and I'm tired. However, if they don't find gravitons at some stage (in other experiments....LHC etc), they're going to have to do some fancy mathematical footwork

[freespace]

Originally Posted by renormalised

I probably didn't read the article properly anyway...being late and I'm tired. However, if they don't find gravitons at some stage (in other experiments....LHC etc), they're going to have to do some fancy mathematical footwork

The string theorists might have to add another dimension to their theories

[renormalised (Carl)]

Originally Posted by freespace

The string theorists might have to add another dimension to their theories

Yeah, the Twilight Zone...which is where I'm heading right now!!!!

[marki]

Originally Posted by renormalised

I probably didn't read the article properly anyway...being late and I'm tired. However, if they don't find gravitons at some stage (in other experiments....LHC etc), they're going to have to do some fancy mathematical footwork

I think these guys will do what they always do when their theories don't work. Write another fairy tale, submerge it in complex mathematics and put the bandaid over the gaping hole. Of course it always helps if no one can test it scientifically for a couple hundred years or so.

Mark

[freespace]

Originally Posted by marki

I think these guys will do what they always do when their theories don't work. Write another fairy tale, submerge it in complex mathematics and put the bandaid over the gaping hole. Of course it always helps if no one can test it scientifically for a couple hundred years or so.

Mark

What do you propose we do instead?

[marki]

A good first step would be to accept we are barking up the wrong tree or simply do not have the technology to deal with the complexities even in the tiny bit of the universe that we can observe. I have no problem with the scientific method or that the universe is expanding at an accelerated rate. There is empirical evidence for that in our local universe and only a fool would deny it. But I do have a problem with the inertia that drives the current accepted theories and how they are put forth as the only possible solution. I fear cosmology is entering the rhelms of psuedo science. That is just my opinion like it or lump it.

Mark

[Karls48 (Karl)]

I like it!

[freespace]

If "accept we are barking up the wrong tree" means "accept our current theories are inadequate", then any 3rd year physics student can tell you this is already the current state of affairs.

As for not having good enough technology, are you saying we should give up because we can't build the machines to test our theories? One must remember that the universe itself is a vast laboratory where events of unimaginable scale and energies play out daily. We need only to point our telescopes in the right places to verify the predictions of our theories. Stellar (pun!) examples would be gravitational lensing and Einstein's Cross.

You are right there is inertia behind existing theories, which isn't surprising given they works so well so often. But this inertia isn't preventing scientists from working on alternatives - you simply do not hear of alternatives because none of them have worked out yet. They are buried in pre-print archives, or in the "Didn't Work Out" tray on some theorist's desk. This gives the impression we aren't trying, when nothing could be further from the truth. However good theories don't grow on trees. It takes extraordinary genius or insight to come up with another general relativity or quantum field theory. As our theories get better, it becomes harder to come up with even better theories.

Proving existing theories being wrong isn't enough. You need a better model to take its place. Further, even if there is a better model, we don't necessarily have to use or teach it except to a few. An example of this is Newton's theory of gravity: we know it is wrong, but it works well enough. So we teach it and use it because frankly general relativity is far too much work for something as mundane as calculating where the cannonball is going to hit.

Cosmology isn't a monolithic theory. Cosmology is a field of study containing many many theories. Experiments such as one in the article helps to weed out the unsuccessful ones or dethrone the reigning model. As long as these experiments continue to be carried out and bad theories thrown away, in my view cosmology remains a science.

Every time an popular theory falters, a hundred theorists' eyes glint.

Cheers,
Steve

[marki]

Originally Posted by freespace

If "accept we are barking up the wrong tree" means "accept our current theories are inadequate", then any 3rd year physics student can tell you this is already the current state of affairs.

As for not having good enough technology, are you saying we should give up because we can't build the machines to test our theories? One must remember that the universe itself is a vast laboratory where events of unimaginable scale and energies play out daily. We need only to point our telescopes in the right places to verify the predictions of our theories. Stellar (pun!) examples would be gravitational lensing and Einstein's Cross.

You are right there is inertia behind existing theories, which isn't surprising given they works so well so often. But this inertia isn't preventing scientists from working on alternatives - you simply do not hear of alternatives because none of them have worked out yet. They are buried in pre-print archives, or in the "Didn't Work Out" tray on some theorist's desk. This gives the impression we aren't trying, when nothing could be further from the truth. However good theories don't grow on trees. It takes extraordinary genius or insight to come up with another general relativity or quantum field theory. As our theories get better, it becomes harder to come up with even better theories.

Proving existing theories being wrong isn't enough. You need a better model to take its place. Further, even if there is a better model, we don't necessarily have to use or teach it except to a few. An example of this is Newton's theory of gravity: we know it is wrong, but it works well enough. So we teach it and use it because frankly general relativity is far too much work for something as mundane as calculating where the cannonball is going to hit.

Cosmology isn't a monolithic theory. Cosmology is a field of study containing many many theories. Experiments such as one in the article helps to weed out the unsuccessful ones or dethrone the reigning model. As long as these experiments continue to be carried out and bad theories thrown away, in my view cosmology remains a science.

Every time an popular theory falters, a hundred theorists' eyes glint.

Cheers,
Steve

Heard all this before Steve, sorry but I do not concur. I have a physical science background though most of my third year physics is a very distant memory and I have not had the need to put it into practice (the old adage if you don't use it you lose it"). But I do remember building a healthy sceptisim toward any theories I studied whilst completing my degrees. I often had my professors on the backfoot when asking questions they could not answer even though they had just given a lecture on it. Do they still teach you to be scepitical or do they just want you to shallow all they expound to be good and true? I can smell a rat from a mile away and this one has an over powering odour. Like I said, it is only my opinion like it or lump it. I believe the funding could be better spent elsewhere. When we have the gear to investigate the problem properly or another intellect of the caliber of Albert I will retract my statement but until then.... If it was up to me I would pull all the funding on this rot PHD's be dammed and concentrate in getting our species out among the stars.

Mark

[sjastro]

Originally Posted by freespace

If "accept we are barking up the wrong tree" means "accept our current theories are inadequate", then any 3rd year physics student can tell you this is already the current state of affairs.

As for not having good enough technology, are you saying we should give up because we can't build the machines to test our theories? One must remember that the universe itself is a vast laboratory where events of unimaginable scale and energies play out daily. We need only to point our telescopes in the right places to verify the predictions of our theories. Stellar (pun!) examples would be gravitational lensing and Einstein's Cross.

You are right there is inertia behind existing theories, which isn't surprising given they works so well so often. But this inertia isn't preventing scientists from working on alternatives - you simply do not hear of alternatives because none of them have worked out yet. They are buried in pre-print archives, or in the "Didn't Work Out" tray on some theorist's desk. This gives the impression we aren't trying, when nothing could be further from the truth. However good theories don't grow on trees. It takes extraordinary genius or insight to come up with another general relativity or quantum field theory. As our theories get better, it becomes harder to come up with even better theories.

Proving existing theories being wrong isn't enough. You need a better model to take its place. Further, even if there is a better model, we don't necessarily have to use or teach it except to a few. An example of this is Newton's theory of gravity: we know it is wrong, but it works well enough. So we teach it and use it because frankly general relativity is far too much work for something as mundane as calculating where the cannonball is going to hit.

Cosmology isn't a monolithic theory. Cosmology is a field of study containing many many theories. Experiments such as one in the article helps to weed out the unsuccessful ones or dethrone the reigning model. As long as these experiments continue to be carried out and bad theories thrown away, in my view cosmology remains a science.

Every time an popular theory falters, a hundred theorists' eyes glint.

Cheers,
Steve

I agree with all your points Steve except Newton's theory of gravity is not wrong....

Steven

[freespace]

The lecturers at the University of Sydney at least are happy to acknowledge their ignorance and problems with successful theories. The answer of "I don't know" isn't uncommon during and after lectures when the smarter students asks tricky questions.

Perhaps attitudes have changed. There seems to be a greater awareness of the philosophy and history of science amongst my professors. I can only say I have seen, and still do not see, evidence of the behaviour you believe to plague the lecture halls - of the arrogant professor who believes his teachings are right and unquestionable.

I doubt diverting funding from such experiments will do anything to put us amongst the stars. The funding for such projects as LIGO is a tiny compared to other national endeavours, and would do nothing to further the goal of making us a space faring species. I do not believe it is a matter of economics, but political will.

As for having the gear to investigate it properly, this is an deadlock attitude. If you don't try to create the gear to investigate it properly, then you will never get the gear to investigate it properly. Imagine if the Wright brothers said "we will wait until they have developed an engine with sufficient power/weight ratio before trying to make a heavier than air flying machine".

[marki]

Originally Posted by freespace

The lecturers at the University of Sydney at least are happy to acknowledge their ignorance and problems with successful theories. The answer of "I don't know" isn't uncommon during and after lectures when the smarter students asks tricky questions.

Thats a refreshing change. However, it's not just the funding thats the problem, it's also the brain power thats being diverted away from manned space flight. I offer you another senario based on your own. Imagine if Oliver left Wilber to his own devices because he wanted to compete in Le tour de france rather then getting himself up amongst the birds. Surley someone would have eventually managed flight but it would have taken longer to develop then it did. With the over population of our home planet and the rapid depletion of resources as well as the destruction of the biosphere I think we can wait to find the answers to the origin of the universe, it is not that important. We need to get off this rock and find a new home or it will all end up being irrelevent. Small advances made now made be of upmost importance when the crunch finally comes.

Mark

[renormalised (Carl)]

I doubt diverting funding from such experiments will do anything to put us amongst the stars. The funding for such projects as LIGO is a tiny compared to other national endeavours, and would do nothing to further the goal of making us a space faring species. I do not believe it is a matter of economics, but political will.

You hit the nail on the head there, although I can think of a few useless areas they pour good money into that gets wasted, which would be better spent on space research, health etc.

[marki]

Originally Posted by renormalised

You hit the nail on the head there, although I can think of a few useless areas they pour good money into that gets wasted, which would be better spent on space research, health etc.

I was wondering how long it would take you to find this Carl .

Mark

[freespace]

Fair points

However, brainpower isn't quite like computing powe, easily adaptable. Perhaps we will do better to train more engineers and scientists instead of poaching on other disciplines.

We should also respect other people's right to work on what they find interesting - perhaps they believe understanding the origins of the universe is far more important than becoming a space faring species.

Cheers,
Steve

[marki]

Originally Posted by freespace

Fair points

However, brainpower isn't quite like computing powe, easily adaptable. Perhaps we will do better to train more engineers and scientists instead of poaching on other disciplines.

We should also respect other people's right to work on what they find interesting - perhaps they believe understanding the origins of the universe is far more important than becoming a space faring species.

Cheers,
Steve

True enough Steve . Viva la revolution, death to all bean counters, political studies students, Law students, commerce students and anyone studying the arts (would have to be after lunch though coz thats when their lectures start ). Now where did I put my garlic and stake?

Mark