Things you'd like to ask a theoretical physicist.

reply to post by zigmeister


"4. String theory accepts that reality consists of 11 dimensions. Most people know of the 4 that we can observe. Given that the only models (at least that I can seem to find) are mathematical, is there any way that these other dimensions can be explained in layman's terms? Is there a model which exists in which the average person can interpret?"

I'm as curious as you are. If there are supposedly 11 different dimensions (to our reality)...........does that not mean within each dimension there are also a score of other dimensions? Dimensions to me would be exponential and unlimited. I am so fascinated, yet clearly not affable on the subject matter.

Great thoughtful post. Answers would be great.

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Originally posted by CaptChaos
Dark energy and dark matter are merely magic pixie dust to force the observations to fit the theories. This is nonsense. Black holes are basically dividing by zero. This is also nonsense. This is the very opposite of science.

This is completely, absolutely, irrefutably, garbage. Nothing you just said makes any sense in any way.

Everything is being forced to reinforce the existing Big Bang theory and other nonsense. The theories are obviously wrong.

Also wrong. As is the rest of your post.

Originally posted by Semicollegiate
Exceptring a high energy destructive event, are any individual quantum particles or atomic nuclei immortal?

If you are asking if they decay, this is a good question (if not it is a terrible question). It is currently not known if all particles ultimately decay into other particles. Generically you would expect that everyone should ultimately decay into some lightest particle unless there is a good reason not to, but it seems that, according to the Standard Model, there is no term in the equations corresponding to the decay of some particles, such as protons. What this means isn't that they can't decay, but if they do decay, it is too infrequent to have been measured yet. Google "proton decay" if you want to read more specifically about this.

Originally posted by CLPrime
Ironically, if gravitons exist, then they, too, produce their own gravitational field. And, then, each graviton in that field would produce its own gravitational field. And each graviton in each of those fields would produce its own gravitational field. And so on.

This is not ironic, this is the opposite of ironic. Expected, we would call it.

Originally posted by 1littlewolf
What is the most current or likely theory in your opinion as to why the 'Big Bang occurred?

Because it could! (Really.)

If the universe is able to tunnel (or arrive through any other mechanism) in the state where the big bang is just about to happen, then it will eventually do it.

Note that, though it is not obvious, the fact that time did not exist "before" the big bang does not effect this argument.

The real question to ask is if the big bang could have occurred any other way. (This answer turns out to be: probably, yes. And it did, and will again, occur differently, producing universes with different laws of physics, and the occur the same way, with these laws of physics.)

Originally posted by brilab45
I'm as curious as you are. If there are supposedly 11 different dimensions (to our reality)...........does that not mean within each dimension there are also a score of other dimensions?

This is not what dimensions are. Dimensions are types of degrees of freedom, not sci-fi scripts.

Originally posted by Moduli
Continued due to character limit:

Originally posted by brilab45
I'm as curious as you are. If there are supposedly 11 different dimensions (to our reality)...........does that not mean within each dimension there are also a score of other dimensions?

This is not what dimensions are. Dimensions are types of degrees of freedom, not sci-fi scripts.

edit on 7-12-2011 by Moduli because: (no reason given)

Like I said, I do not understand. Grateful for those that do. Guess I need to be more assertive in my own research. However, can you please explain to a layman what degree's of freedom mean.

I know, for you big thinkers...things seem simple. Not for me though. Just a simple explanation please????

Thank you.

Oh, I do appreciate you for actually replying.

Originally posted by Moduli

Because it could! (Really.)

If the universe is able to tunnel (or arrive through any other mechanism) in the state where the big bang is just about to happen, then it will eventually do it.

Note that, though it is not obvious, the fact that time did not exist "before" the big bang does not effect this argument.

I don't understand how something could 'arrive' at a point where something is about to happen without time. For in order for something to change, does not time need to exist. Or is this something to do with the fact that there is no 'space'. But then I am still confused as for something to change or 'arrive' as you put it, I would assume both time and space to be necessary

The real question to ask is if the big bang could have occurred any other way. (This answer turns out to be: probably, yes. And it did, and will again, occur differently, producing universes with different laws of physics, and the occur the same way, with these laws of physics.)

Why do you say 'probably'? How could it have occured differently? What do you mean by differently?

And when you say "it did and will again" does this mean that somewhere in physics there is an indication there is or will be different universes occuring concurrently to ours with different laws of physics?

Originally posted by brilab45
Like I said, I do not understand. Grateful for those that do. Guess I need to be more assertive in my own research. However, can you please explain to a layman what degree's of freedom mean.

I can't explain it without using some kind of math. But they are basically certain kind of variables that show up in functions, like f(x), f(x,y), etc...

Originally posted by 1littlewolf
I don't understand how something could 'arrive' at a point where something is about to happen without time.

It's not that there is no time at all, it's that the time measured by our universe did not exist then. In some sense, there is no well-defined continuation of time before the big bang, into time after it. So, there are times before and after, they just have nothing to do with each other.

Why do you say 'probably'? How could it have occured differently? What do you mean by differently?

It's technical, but for several reasons I say "probably." Largely, because we don't understand the set of possible allowed configurations that a universe could start in. There is good reason to believe that this set is very large, but it is not well understood, so there could be a small number (or even one) mathematically consistent universe, a large but finite number, a countably infinite number, or an uncountably infinite number.

By "differently" I mean different laws of physics: types of particles, forces, etc.

reply to post by brilab45

However, can you please explain to a layman what degree's of freedom mean.

he means that dimensions refer to the maximum possible directions you can move in. think of a piece of paper with 2d creatures living on it. they can go forward, and backwards, then left, and right. they can't go up or down. the two dimensional plane they exist on CAN move through higher dimensions, but they themselves are unaware of any other directions than the two they can move along.

humans are similarly limited by three dimensions. we move linearly though the 4th dimension and experience this change as time. in the same way, 2d pictures can become movies when moved through the 3d dimension (think reel of film projecting images very rapidly).

instead of 2d pictures, we're 3d cubes. each "cube" is like a frame from a movie, and time is us moving through the 4th dimension similar to how the 2d pictures move through the 3d dimension.

time is essentially an illusion created by our limitations.

Originally posted by Moduli

It's not that there is no time at all, it's that the time measured by our universe did not exist then. In some sense, there is no well-defined continuation of time before the big bang, into time after it. So, there are times before and after, they just have nothing to do with each other.

Thank you for giving me a easy to understand answer over something that's bugged me for years. So essentially there always has been 'time' just not in a way we understand it now.

Does this same concept apply to space? I've always been intrigued by the interelatedness of time and space. In your opinion is it possible for one to exist without the other? For as I see it time is change, but in order for change to occur there needs also to be space in order for that change to occur. Is this correct?

reply to post by 1littlewolf

that isn't known. no one knows what was before the big bang, there are only theories. no data or evidence.

Originally posted by 1littlewolf

Originally posted by Moduli

It's not that there is no time at all, it's that the time measured by our universe did not exist then. In some sense, there is no well-defined continuation of time before the big bang, into time after it. So, there are times before and after, they just have nothing to do with each other.

Thank you for giving me a easy to understand answer over something that's bugged me for years. So essentially there always has been 'time' just not in a way we understand it now.

Does this same concept apply to space? I've always been intrigued by the interelatedness of time and space. In your opinion is it possible for one to exist without the other? For as I see it time is change, but in order for change to occur there needs also to be space in order for that change to occur. Is this correct?

Moduli, good answers and we have evidence to support much of what you said.

However, answers about what happened before the big bang are highly speculative, are they not?

In other words, we have no evidence that time in any form existed before the big bang, do we? I thought events prior to the big bang are pretty much unknown and open to speculation?

reply to post by Bob Sholtz


Thank you for the reply. Of course my little mind will have to absorb and re-read your post. I am grateful that you replied.

My questions are 1: How does water go down the toilet directly on the equator?

2: What are the vertical lines perpendicular to one side of a nuclear mushroom cloud and why are they only on one side?

yay! a really for real stuffed-up-full-of-himself-"theoretical" physicist!

Originally posted by Moduli
....the way things move under a force is dictated by the Euler-Lagrange equations.....

uhhhh....begging yer pardon, but equations DICTATE nothing. they are a cheap imitation from feeble minds. (mine of course being even more feeble.) i think you may have gotten so wrapped up in the "truth" that your credentials for "theoretical" are fading.


but, since you're here, I would very much like to receive a satisfying answer to why the negative solutions (of the square roots) in the klein-gorodon's equation are determined as "meaningless", and how such meaninglessness can be contrasted against something so useful as the positive solutions from the exact same equation?

and, considering that my question may shed some light on the OP's reverse-entropy question, perhaps you wouldn't mind revising your answer to his question in the spirit of full disclosure?

Originally posted by tgidkp
uhhhh....begging yer pardon, but equations DICTATE nothing. they are a cheap imitation from feeble minds.

Nothing about this makes any sense. What do you think the difference between pre-enlightenment and post-enlightenment thinking is? (That's rhetorical, don't bother to answer, just figure out the answer. Preferably by years of studying actual science.)

but, since you're here, I would very much like to receive a satisfying answer to why the negative solutions (of the square roots) in the klein-gorodon's equation are determined as "meaningless", and how such meaninglessness can be contrasted against something so useful as the positive solutions from the exact same equation?

Because they're nonsense. They correspond to solutions which violate the rule that probabilities add up to one, if you interpret them naively. The correct answer is to interpret them with the appropriate (and more sophisticated) analog of the Dirac sea for spin-0 particles, which is what quantum field theory is all about.

and, considering that my question may shed some light on the OP's reverse-entropy question, perhaps you wouldn't mind revising your answer to his question in the spirit of full disclosure?

Being a completely different thing, it sheds no light on it whatsoever.

Originally posted by Arbitrageur
Thank you for giving me a easy to understand answer over something that's bugged me for years. So essentially there always has been 'time' just not in a way we understand it now.

Not really... it's just like time here, it's just not related to it...

Does this same concept apply to space?

More or less. The space we have now is not connected to any other spaces.

I've always been intrigued by the interelatedness of time and space. In your opinion is it possible for one to exist without the other?

There's no problem at all with this, they can certainly exist without each other. The way the laws of physics work, they are related to each other, though. But there was no reason it could not have been different.

However, answers about what happened before the big bang are highly speculative, are they not?

In other words, we have no evidence that time in any form existed before the big bang, do we? I thought events prior to the big bang are pretty much unknown and open to speculation?

There isn't any known way to measure anything that happened before the big bang, but that doesn't stop us from understanding how it happened. Mathematical consistency is very powerful and constraining.

Originally posted by ludshed
My questions are 1: How does water go down the toilet directly on the equator?

2: What are the vertical lines perpendicular to one side of a nuclear mushroom cloud and why are they only on one side?

what?

How are we even alive???

like there are sooo many processes happening every second. I can't understand how they all work together so peacefully admist what should be seemingly endless chaos...

like our blood flowing, air intake, and at the same time it's all in corelation with how the planet is intaking carbon dioxide and expelling oxygen at just the right levels? and the atmosphereic pressure, EVERYTHING. HOW. ?

A dimension is a quality that can have any value and not affect another dimension.

You could be anywhere on earth at any given time, so time is a dimension separate from 3d space.

You could have any normal body weight any where on earth so you body weight could be a dimension and it would be a small dimension.

You know, the thin lines that look like smoke columns that go from the ground to the sky next to a nuclear explosion. They're always on one side.

reply to post by ludshed


1. The water swirls in the direction of the under-rim spouts placed there by the manufacturer.

2. The lines are smoke rocket trails , sent up before the test to help measure the pressure-wave of the blast.

reply to post by Moduli


wow. you really ARE that useless, aren't you? (rhetorical, don't answer.)

FYI. I have already been studying science for years now. the university kind, too...not just Mickey mouse. but thanks for the condescension and outright dismissal ...

...you should probably go back to lurking and SILENTLY laughing at us all.

Absolutely fantastic posts so far. S+F for this thread and who knows - maybe we really focus all our thoughts onto something strange and find a solution for a problem. It is often just by chance that science got another breakthough

My question to those who know better than I do would be:

If the Simulation Argument is true (I don't say that I believe in it but it is an interesting theory) do we have any possibility to find out what is really behind this simulation? If anything around us is simulated (no matter who runs this simulation) can we expect to find a hole in this simulation to look behind all the parameters set up for our world to gain insight into the real physical world behind it?

Originally posted by ludshed
My questions are 1: How does water go down the toilet directly on the equator?

2: What are the vertical lines perpendicular to one side of a nuclear mushroom cloud and why are they only on one side?

Question #1 is based on a myth that water goes down the drain in different directions in different hemispheres.

If the body of water is the size of a toilet. the Coriolis effect isn't the determining factor for the direction of rotation. A toilet can drain in either direction in either hemisphere so of course on the equator also. If you're draining a larger body of water like perhaps an olympic sized swimming pool, then it's perhaps large enough for the hemisphere to be a significant enough influence to make a difference. In that case, any small random external influence could determine the direction on the equator, probably something like a small breeze which is partially blocked by a building near the pool so it doesn't blow on the water uniformly.

Claim: The Coriolis force influences which direction water spirals down drains and toilets in different hemispheres.

Status: False.

Originally posted by UnixFE
If the Simulation Argument is true (I don't say that I believe in it but it is an interesting theory) do we have any possibility to find out what is really behind this simulation?

That would depend on how good the simulation is. Someone probably watched "The Matrix" movies too many times, but those movies are a pretty decent Hollywood representation of how a nearly perfect simulation might have flaws that some people might discover. Pretty good science fiction stuff but it doesn't pass the Occam's razor test.