Theory vs fact

[xelasnave]

from that site....

What is the evidence for the Big Bang?
The evidence for the Big Bang comes from many pieces of observational data that are consistent with the Big Bang. None of these prove the Big Bang, since scientific theories are not proven. Many of these facts are consistent with the Big Bang and some other cosmological models, but taken together these observations show that the Big Bang is the best current model for the Universe. These observations include:

The darkness of the night sky - Olbers' paradox.
The Hubble Law - the linear distance vs redshift law. The data are now very good.
Homogeneity - fair data showing that our location in the Universe is not special.
Isotropy - very strong data showing that the sky looks the same in all directions to 1 part in 100,000.
Time dilation in supernova light curves.

alex

[Brian W (Brian)]

[quote=Zuts;293350]The fact is that scientific experiments which 'prove' a theory are only deemed to be good experiments if they are independently verifiable and reproducible.

hi Paul, let me try again. I grant you that to 'prove' water boils at a certain temperature scientists time and again boiled water and found that under similar circumstances water would boil at a similar temperature. But what they did not and could not prove was that it would always happen exactly the same way. There is an uncertainty factor and though you can make it really really really tiny you can never totally eliminate it. Which may be one reason why scientists prefer to call things 'theories' rather than facts.
Brian

[Zuts]

[QUOTE=Brian W;293462]

Originally Posted by Zuts

The fact is that scientific experiments which 'prove' a theory are only deemed to be good experiments if they are independently verifiable and reproducible.

There is an uncertainty factor and though you can make it really really really tiny you can never totally eliminate it. Which may be one reason why scientists prefer to call things 'theories' rather than facts.
Brian

Hi Brian,

I notice you are in the Phillipines.

After long effort and observation and repeatable experiments using the scientific method scientists verified the Bernoulli principle. Engineers used this principle and again after long periods of experimentation they designed an aeroplane wing which allows aeroplanes to stay in the air.

Now, admitedly aeroplanes do fall out of the sky, but not because the Bernoulli principle suddenly and for no apparent reason ceases to be true.

So, if ever you leave the Phillipines i would advise you to take a boat as who knows, maybe at 30,000 feet 'There is an uncertainty factor and though you can make it really really really tiny you can never totally eliminate it' the Bernoulli principle may somehow become untrue and your plane may plummet to the ground

Then again, it may not because the observed repeatable experiment that things fall to the ground at a certain rate v= at may also give up the ghost and you may find yourself floating around up there.

Quantum effects are affected by the Heisenberg uncertainty principle but i dont believe these effects are visible, measurable or indeed relevant on the macro scale.

Paul

[xelasnave]

and that runs into the following.....

The observations listed above are consistent with the Big Bang or with the Steady State model, but many observations support the Big Bang over the Steady State:
Radio source and quasar counts vs. flux. These show that the Universe has evolved.
Existence of the blackbody CMB. This shows that the Universe has evolved from a dense, isothermal state.
Variation of TCMB with redshift. This is a direct observation of the evolution of the Universe.
Deuterium, 3He, 4He, and 7Li abundances. These light isotopes are all well fit by predicted reactions occurring in the First Three Minutes.
Finally, the angular power spectrum of the CMB anisotropy that does exist at the several parts per million level is consistent with a dark matter dominated Big Bang model that went through the inflationary scenario.

alex

[Geoff45 (Geoff)]

Many "facts" can only be interpreted in terms of a theory. If you point at Rigel and say "There it is--fact", you are relying on the theory that light travels in (approximately) straight lines. If you say that the sun has such and such a temperature, you are using spectroscopic theory. There are very few (if any) "facts"
Geoff

[Brian W (Brian)]

[quote=Zuts;293469][quote=Brian W;293462]

Hi Brian,

I notice you are in the Phillipines.

After long effort and observation and repeatable experiments using the scientific method scientists verified the Bernoulli principle. Engineers used this principle and again after long periods of experimentation they designed an aeroplane wing which allows aeroplanes to stay in the air.

Hi Paul, you are correct that I am in the Philippines. You are not correct that wings allow airplanes to stay in the air. As a retired commercial pilot here I speak with some authority. It is controlled power that keeps an airplane in the air. Reduce an aircrafts speed below the safe minimum airspeed for that aircraft and you are going to fall down and go boom. Might I suggest that science demands a repeatable and verifiable test result to reduce the probability of having a different effect noted. but i do not believe any scientist would suggest that the chance for a different result is absolute zero. It matters not if it is science or religion at one point or another both world views require a leap of faith because there is always that little nagging doubt or possibility that what you believe just ain't so. Like the old song has it ' the stories your liable to read in the bible just ain't necessarily so.' Physics is now once again in search of the Holy grail of a unified theory because any and all theories today fall apart when pushed to hard.

I will say it again there are no 'facts' in science just things that more or less explain what we experience.

Brian

[Karls48 (Karl)]

Hi Brian, on completely different note. I plan to move to Philippine in about five years time. I have been there serval times before and night sky was just brilliant, especially in Mindanao. But also many nights were cloudy. Any thoughts on astronomy in Philippines? Also do you know how Philippine customs threat importing telescopes there?

[xelasnave]

Originally Posted by ghsmith45

Many "facts" can only be interpreted in terms of a theory. If you point at Rigel and say "There it is--fact", you are relying on the theory that light travels in (approximately) straight lines. If you say that the sun has such and such a temperature, you are using spectroscopic theory. There are very few (if any) "facts"
Geoff

I think what you put forward in your last sentance is a fact.

alex

[Brian W (Brian)]

Originally Posted by Karls48

Hi Brian, on completely different note. I plan to move to Philippine in about five years time. I have been there serval times before and night sky was just brilliant, especially in Mindanao. But also many nights were cloudy. Any thoughts on astronomy in Philippines? Also do you know how Philippine customs threat importing telescopes there?

I amwered this one privately. But if anyone is wondering dark skies and no sub zero temperatures make for great astronomy when then clouds clear off.

Brian

[astroron (Ron)]

Does this article help in this discussion? http://www.eso.org/public/outreach/p.../pr-04-08.html
I am sure someone will be able to get something out of it
Ron

[Brian W (Brian)]

The article clarified things for me re putting too much faith in obvious facts and principals. Seems with what they have explored we either have to rethink our understanding of gravity or include multiple new dimensions of some sort to make the new understanding cohesive. as some one in the bible puts it (more or less); our understanding is similar to looking through a smoky mirror you can get the general idea but the finer details are a little obscured.
Brian

[xelasnave]

Originally Posted by astroron

Does this article help in this discussion? http://www.eso.org/public/outreach/p.../pr-04-08.html
I am sure someone will be able to get something out of it
Ron

Are you pulling my chain Ron.
Dark energy is my favorite thing
alex

[xelasnave]

When the mythical force of attraction has been cast out and recognition that gravity does not suck but pushes all things will become clear.

Space controls matter..matter does not control space...in my humble view and at odds with all others
alex