what is the biggest most fundamental question in all of physics?

Oldfart

Agree, but I was talking about T=0, not <0.

tarnhelm

I think, as in so many areas, there's a convergence between physics and philosophy. Philosophers in the past have argued that unless there is some uncaused cause external to the universe, then the universe must be causa sui and have persisted through infinite time up to now. The notion of an uncaused event is anathema to physics, as is the notion of belief in some unseen metaphysical entity. Therefore, physics and a philosophical perspective both demand that there is no spontaneous ex nihilo creation. It is contrary to the foundational principles of physics that the universe should have just popped into existence with a cause. So there is no such thing as t<0. If something else caused our universe, then its contours will surely one day be divined just as surely as we are now probing the contours of events 14 billion years ago.

And in any case, it's not really a question for philosophers because that sort of speculation was the preserve of philosophers centuries ago. Nowadays philosophers tend to be interested in things like logic, language, and the mind. The real heirs of that sort of philosophy are modern theoretical physicists.

John15

I think " why is there something rather than nothing " or make a universe out of absolutely nothing, says it all you could also add where does God fit in as well

EmpaDoc

I think you put it well. There is no consensus in physics about "the fundamental question".

Particle physicists would argue that it's something like "how to combine relativity and QM", which would then hopefully lead to the "theory of everything" governing the behavior of all fundamental particles (and then, some think that string theory is the answer to that). This is of course often heard in popular media.

On the other hand, a condensed-matter or non-linear physicist, for example, would argue that understanding phenomena is more important than understanding specific cases. Like broken gauge symmetry which underlies both superconductivity and the Higgs mechanism. With this view, it is hard to formulate a single "ultimate question".

Nobel Laureate Robert Laughlin's nice book "A Different Universe: Reinventing Physics from the Bottom Down" is an excellent critique of the common particle-physics view.

fellupahill

Who was the physicist that said "after the big bang is the job of science, before the big bang is the job of theologists." Not an exact quote, but hopefully someone can make the connection. Ive read it somewere, a while ago.

Claude Bile

1. Why don't General Relativity and Quantum Physics agree?

2. How did Justin Beiber ever become popular?

Claude.

HallsofIvy

"String theory" still needs an experimental basis. I would say that the most important fundamental problem is combining quantum theory and relativity- the "unified field theory".

dpa

well extend it to what is fundamental problem in physics NOW?
That would definitely be GUT/UFT
or add FTL travel to conquer space.

Physics is more of EXPLAINATION OF NATURAL PHENOMENA.
ANOTHER age of successful space exploration and beyond will bring in new phenomenons.

sophiecentaur

Whatever question you formulate, its answer will not be the answer to 'everything'. Why do I say that? Because, however long we take and however much we pool our own personal awarenesses, there is a limit to the degree to which we can analyse and understand ourselves.
I guess the best we can do is to come to terms with that basic situation but not to 'just give up'. Keep swimming or we drown.

And could someone explain to me why 'Space' and its conquest are supposed to be, in some way, the ultimate goal? That always sounds to me too much like the Wild West and Cowboy movies. The really important stuff is going on Inside our Heads.

dpa

Conquest of space will provide fuel to the brain we have. Fuel to open new vistas to our thought processes.
Well i am not going to believe that everything is inside our head after the clear evidence of evolution of beings and creation of our brain from chemicals.
Its difficult to imagine EVEN THAT to be hollogram created by brain.
Where would evolution/bigbang and everything outside that fit in?
There might be no end to curiosity but at least I cant remain without thinking.

DennisN

what is the biggest most fundamental question in all of physics?

Wonderful question! However, I refuse to give only one answer, so here comes ten :

1. Can Quantum mechanics be joined with Relativity?
2. What is the most correct interpretation of Quantum mechanics?
3. When will QM & Relativity be replaced with even better theories? Will they? The history of science seems to say yes...
4. Why does the arrow of time point in only one direction?
5. What is the origin of mass (Higgs?) and how does the interaction of gravitation work (gravitons?)?
6. What is the origin of charge? Can it in any way be related to energy? Why does it not care about relativity?
7. Do the electron and/or the quarks have any substructure?
8. What is the true nature of vacuum? Is it empty or not?
9. Are there more spatial dimensions than three? How could we find out? Can we ever?
10. Is there only one Universe? Can we ever answer that question?

Here is a good link too: Open Questions in Physics.

jnorman

hmmm - to me, it boils down to "what is a field?"

since there is basically no-thing there (ie, all fundamental particles are point particles with no volume, just properties), and the idea that "particles" are simply excitations of a given field, and since, from what i can tell, there is no understanding of what a field actually is or how it operates (virtual particle exchange explains pretty much nothing at all), i would say that is my most basic question.

sophiecentaur

You make the very important point that it's YOUR most basic question and that's the point. We all have different ones - which makes life interesting.

CaptFirePanda

Does this TI-36X Pro make me look fat?

AnTav

I can't tell you what the most puzzling question in physics is now, but I can tell you what it will be probably like in a year or so.

"And now? How do we cope with this?"

You have to picture some distressed faces saying that.

DennisN

At least I think there are some distressed faces today saying "Why didn't we check if that cable was properly connected?".

DennisN

I just want to add that I think jnormans question is a really good one too;