Making sense of the Universe

Discussions on classical and modern physics, quantum mechanics, particle physics, thermodynamics, general and special relativity, etc.

Making sense of the Universe

Postby rajnz00 on April 28th, 2021, 10:35 pm 

Space-Time I am told is a kind of a medium in which mass exists. Mass, when it is around, bends space-time. Symbiotically mass "tells" spacetime how to bend and spacetime "tells" mass how to move. But what exactly is mass? The Higgs boson we are told, accounts for it, but what is it? The electron has mass but only 1/1840 or some such figure the mass of the proton. Why does some stuff, like the proton have more mass than the electron? Is there a fundamental unit of mass out of which all other masses are made of? And what is spacetime made of? Must be made of something if it bends, vibrates and is dragged around.
And Time, is it made of events? So how exactly does it get tied up with space to form spacetime?
I read somewhere that when you fall into a black hole according to General Relativity you get crushed into a "singularity" but the singularity is Time and not Space. So the does Time get separated from Space, if it is Time that is the singularity and not space?
What about dark energy. Energy is equivalent to mass so shouldn't that be increasing the mass of the Universe and cause gravity to crunch it? Instead, it seems to acting like an anti-gravity substance and expanding it?
If it accounts for 74% of the stuff of the universe, why is it not overwhelming gravity on Earth?
rajnz00
Member
 
Posts: 386
Joined: 28 Dec 2016


Re: Making sense of the Universe

Postby rajnz00 on May 8th, 2021, 12:41 am 

Something is not quite right in the state of our fundamental theories. General relativity explains the bending of light and, using both Special and General Relativity, GPS can tell us, within a foot or so, our position, so I suppose that is pretty accurate.

But Quantum Physics is a bit of a Hodge-podge. You have Quantum Mechanics, which kind of explains Newtonian mechanics? Not too sure about that. Has Quantum Mechanics ever been used to predict the trajectory of a projectile with more accuracy than Newton's equations? I doubt it. Then you have the Quantum Field theory which is separate from Quantum Mechanics and no one seems to understand it very much. Both seem to work in their own spheres, pretty much like Newtonian physics does in its sphere. But to understand, or maybe "work with" is a better term, the Quantum Field theory, we have to use, apparently, something called the Yang-Mills Gauge theory. So that gives an explanation of the interaction between Quarks and the Strong Nuclear Force. But that's not the end. To explain light we have to use the Perturbation Theory to explain parts of it and the Lattice Gauge theory to explain different parts of it.

But then we have something called the "Mass-Gap" problem. (that thing called Mass, no one seems to know exactly what that is). Quantum particles have finite "mass" but waves travel at the speed of light and light, though a particle can have no mass. Apparently, quantum particles have a property known as mass-gap. No one knows what it is, but using it explains the strong force interactions. Judging by its name, it must have something to do with mass, but why the 'gap"?

Quite a hodge-podge.

The Proton has about 1840 times the mass of the Electron. But the Proton is composed of two Up Quarks and one Down Quark, each of which have mass. So when you add up the masses of the Quarks, you get only 1% of the mass of the Proton. Mass doesn't go away. Becomes tiny but remains.

Then we have the Law of Conservation of Energy, which seems to underpin all of physics. Emmy Noether established mathematically that when you have a conservation law you have a corresponding underlying symmetry. The conservation of energy is a consequence of the uniformity of Time on the scale of the Universe, (according to Peter Atkins).

So this seems to be back to Newton's concept of Universal time that ticks away inexorably and uniformly in the background.

So here we have the General Theory of Relativity that subsumes Newton's laws of mechanics from the top and Quantum Mechanics which does so from the bottom. We are in the middle and Newton's mechanics works perfectly well for us. But The General Theory can't descend into the Quantum Mechanics at the bottom nor can Quantum Mechanics ascend into General Relativity. Somewhere in between there must be a boundary where just beyond one theory prevails over the other. Has this boundary ever been tested out?

Then General Relativity also - we need inflation to explain the Universe and get utterly at a loss when it comes to singularity. Seems to be a bit of a hodge-podge too.

I think we should only trust the theories so far, and if they predict absurd things like the Block Universe look for the obvious flaws in such predictions.

As a poet put it once - One thing I know that Time flies. One thing is true, the rest is lies. A rose that once has bloomed, forever dies.
rajnz00
Member
 
Posts: 386
Joined: 28 Dec 2016


Re: Making sense of the Universe

Postby charon on May 8th, 2021, 5:00 am 

The trouble is your enquiry is too general. It's encompassing practically every known facet of universal science. What are we going to do? Reproduce the entire Encyclopaedia Britannica here in answer to you? And explain things that are far better explained in science websites?

Try a smaller, particular query you have and maybe someone can explain that. If you can't find it decently explained elsewhere, that is.
charon
Resident Member
 
Posts: 2800
Joined: 02 Mar 2011


Re: Making sense of the Universe

Postby Mossling on May 9th, 2021, 10:56 pm 

Charon wrote:The trouble is your enquiry is too general.

Because it's no fun if you don't have a target to randomly shout "nonsense!" at, is it? Lol.
User avatar
Mossling
Active Member
 
Posts: 1477
Joined: 02 Jul 2009


Re: Making sense of the Universe

Postby TheVat on May 10th, 2021, 1:30 pm 

Suggesting a question with a somewhat narrower scope was hardly a shout of "nonsense." Indeed, a physics moderator like Jorrie, might well have made the same suggestion.
User avatar
TheVat
Forum Administrator
 
Posts: 7877
Joined: 21 Jan 2014
Location: Black Hills


Re: Making sense of the Universe

Postby curiosity on May 16th, 2021, 3:57 pm 

Mass, when it is around, bends space-time. Symbiotically mass "tells" spacetime how to bend and spacetime "tells" mass how to move.


And what is spacetime made of? Must be made of something if it bends, vibrates and is dragged around.


What about dark energy. Energy is equivalent to mass so shouldn't that be increasing the mass of the Universe and cause gravity to crunch it? Instead, it seems to acting like an anti-gravity substance and expanding it?]


If you're looking for stock answers to the above three questions you have posed, there are numerous videos on YouTube explaining what the current consensus is. If you (like myself) find the stock answers unsatisfactory, then it is probably better to read what Einstein and Minkowski had to say about Space-time.

Minkowski said... Henceforth space by itself and time by itself are doomed to fade away into mere shadows and only a kind of union of the two will preserve an independent reality

Einstein said... When forced to summarize the general theory of relativity in one sentence..
Time, space and gravitation, have no separate existence from matter.

In these two examples, Minkowskis' statement is certainly unambiguous, while Einsteins' is (unfortunately) open to interpretation. (with regard to the relationship between gravitation and Matter.)
To propose that matter (Magically ???) bends space time, ( which he appears to do,) by not offering up a valid explanation for how it supposedly does so, was indeed very remiss of a genius with Einsteins' standing.

I wont elaborate on my personal beliefs concerning this fascinating subject, until I am sure of which forum I should be posting on, but I will certainly welcome criticism of my thoughts once I reveal them!

Time for my evening stroll now... So its goodnight from me!
curiosity
Member
 
Posts: 429
Joined: 19 Jul 2012



Return to Physics

Who is online

Users browsing this forum: No registered users and 30 guests