Expert: Tom Whiting - 12/31/2009

Question
QUESTION: "Hi,i have heard scientists have no evidence for a graviton but beleive it to be real,as a force carrier for gravity. Why? I understand there must be force carriers for other forces. But i thought we had learned that gravity is a curvature in spacetime and as such no force needs to be carried; matter just follows this curvature/geometry. So,why is there speculation about a graviton? My next question is perhaps metaphysics. Nevertheless... the universe has been likened to a balloon to explain expansion of space [no central point and all galaxies getting further from each other]. If we took that a bit further and said that the air being blown into that balloon provides the expansion of that balloon,the air being not part of the balloons dimensions. Could that not be likened to our universe too? That is,it could be pointless looking for dark energy. The energy inflating our universe may be an external force,not in our dimensions,similar to the air acting on the balloon. Thanks again for your time Regards Richard (again)!

ANSWER: Second question first....the balloon analogy is a poor one conceived in the early days, butit breaks down easily, like you said, air is needed, and even more troubling, the 'dots' painted on the balloon skin, representing galaxies, the dots also expand, so this is a very erronous
analogy.  A far better example is a raison bread rising in the oven, the non-expanding raisons representing the galaxies. As the bread rises, notice that every raison is receding from every other raison, and the farthest raison is receding the fastest. In addition, it doesn't matter which raison you choose as our Milky Way, it is happening to any and all raisons. So all observers everywhere are seeing the same proportional recession.  Lately, we thought that someone was turning the heat of the oven down... the rate of expansionwas slowing. Today we know that 'someone' is actually turning up the oven heat, so the expansion is actually accelerating.  (But is the acceleration also...accelerating?  We don't know that, as yet.)  So the end cannot be a Big Crunch as orignally thought... it's a race between a heat
death (all fuel used up) or the Big Rip... the expansion occurs so fast that eventually space
expansion will rip apart even atoms at the very end.  Of course, all this is perhaps hundreds
of trillions of years from now. (We've only just begun as the song says, 13.7 billion years
ABB is starting to seem like a very short time)!

The graviton is the hypothetical particle at the quantum level to explain, as you said, the
curvature of space-time continuum.  That's a little out of my field, but the curvature does
not delete the need for a graviton at the quantum level, so the search goes on for it.
(As does the need for the Higgs boson too).  See
http://en.wikipedia.org/wiki/Graviton
Clear Skies,
Tom Whiting
Erie, PA

---------- FOLLOW-UP ----------

QUESTION: Hi Tom,more a general feedback and thankyou rather than a question. This has been a general interest of mine since i was a child and i read extensively about cosmology. I understand most of the general concepts but alas not the maths! I feel i have the same thoughts as you on religion and unscientific practice. I have been very grateful to have had feedback from someone with greater knowledge than myself. I have read some of your other answers and hope that people such as myself who speculate about things without doing the 'groundwork' are not too annoying! For myself, i have in my own limited way. I have the utmost respect for scientists/physicists. I thought i saw in one of your answers your belief that we were in a black hole unlikely. With great respect,and speculation i know,i believe circumstantial evidence to be pointing that way. For one,this universe started with a singularity; the only singularity we know of is in a black hole. Secondly, so many equations we try to use to explain our universe breakdown with singularities or infinities,exactly as happens when describing a black hole. I know this doesnt settle the argument!! When talking of multiverses etc,this would,to me,seem the best mechanism. Thankyou so much for your time Tom. Clear.....and Dark skies to you sir    Kind Regards  Richard

ANSWER: That's just my personal opinion, but I could be wrong... (how does one test for that?)
Well, perhaps we are inside a black holed Universe...I've heard that suggested before.
Perhaps not, either.  In any case, so what?  What could we do about it, and really, what
difference does it make?  None. Nothing we could do about it anyway.
(Black holes don't expand rapidly, like our Universe is doing, so it's not quite an exact analogy).

In any case, we're still "locked in" inside... the influence of the Big Bang outcome, so all their hypothetical parallel universes and multi-universes are not visible or not visit-able from our vantage point anyway.  So all that talk about multi-universes is just academic;
it just makes for vivid imaginations and good sci-fi movies.  But it's meaningless for our
real world. We can't even get to the nearest star at only 4.3 lightyears; how would one
ever get "outside our Universe?"
Clear skies,
Tom Whiting
Erie PA

---------- FOLLOW-UP ----------

QUESTION: Hi Tom,i have heard many top phycicists speculate about multiverses etc and i guess its for them to design experiments! I guess it would be indirect methods such as they may have to with dark energy and matter. The good thing about multiverses/dimensions is they are supposedly right next to us and not light years away. I believe the many steps we will make in the future will be from looking inwards rather than outwards. Experiments such as the LHC will reveal some interesting things im sure. The 3-slit experiment and quantum theory,are the result of,if not multiverses,something very weird! I believe these matters will be testable in the futeure and so be real science. I think if other universes have some relation/effect with ours there may be experimental testing of this. Of course,if there is no relationship then that wouldnt be possible. What difference does it make if we are in a steady state or big bang universe? What can we do about that? The answers to that are the same as the answers to 'was the big bang a result of a black hole forming in another dimension.' Black holes are formed rapidly and presumably a lot of energy goes inward as well as outward at time of formation. I still feel the analagy stands up well. Your previous answer about location and properties of a black hole will probably deny testing of the theory,at least, in the way i thought. I dont feel the question is academic anymore and not all science fiction is bad. Arthur C Clarke wrote science fiction and as long as we can distinguish between entertainment and proper scientific endeavour no harm done. Unfortunately,many cannot differentiate. I do my very best to! Kind Regards  Richard

Answer
Oh, I'm a big fan of good sci-fi, especially the TV series of Startrek.  However, later cast
members' stories started going way out really bizarre, so I lost interest. To me, fiction has to
be at least reasonable and doable and at least remotely possible.  Sometimes they just go too
far out for me...like with parallel or multi-universes where we allegedly can change places
with our identical, but anti-matter "twin"... or going ahead or back in time...stuff like that.
I try to keep facts and reasonable fiction straight, and separated from way out stuff, and
metaphysics... so Yes, I do my best too. I love Arthur Clarke, especailly the short story about
"The Star".
I don't buy into multi-universes right next door to us, except down at the quantum level...same
for wormholes, only at the quantum level, not our macro level.  Same for multi-dimensions, all
down at the Planck distance and time.
For what it's worth,
Clear Skies,
Tom