Thread: pulsating universe

Could you elaborate?

Dark matter is really only a mathematical object at the moment; a placeholder for a proper theory.

The dark matter could be matter in other parallel universes. Then we should be two dimensional creatures and not be able to see the other universes even if they are right here, they would be in different dimensions.

I think it could just turn out to be some kind of heavy particle.

Originally Posted by Xei

I think it could just turn out to be some kind of heavy particle.

It might.

Originally Posted by JustSoSick

It might.

Yep.

Originally Posted by JustSoSick

The dark matter could be matter in other parallel universes. Then we should be two dimensional creatures and not be able to see the other universes even if they are right here, they would be in different dimensions.

isnt that sort of string theory? according to string theory there are like 12 other dimentions or something.

Originally Posted by slash112

isnt that sort of string theory? according to string theory there are like 12 other dimentions or something.

Not quite. String theory look at particles not a spots, but as strings. 'Strings' that can be open or closed. Open stay attached to our universe, closed can travel between universes.

I believe we see in two dimensions, we can`t see up. For eksample, we are in a sheet of paper and there are several papers on top of us, but we can`t see them.

Well we live in 3D so... there is another box, rather than a paper on top of us.

Originally Posted by Xei

Chayba don't pretend to understand astrophysics; you don't.

My theory explains gravity, your theory doesn't. As long as you can't explain gravity except for the three word explanation of "bending of space-time" you shouldn't be so confident that your theories are correct, because you don't even have a theory for gravity. Don't you get it?

To me, you're very much like one of those people of the Dark Ages that keeps shouting that the earth is flat. It's nothing but rusted beliefs based on nothing. But ok I'll admit you're intelligent enough. After a while, when you understand science more, you will eventually come to the same conclusions as me.

My theory explains gravity

Go on then.

And even if you did attempt; I've already said that your aether theory is completely contradicted by actual empirical evidence. I think you're the one who doesn't get this science business.

As long as you can't explain gravity except for the three word explanation of "bending of space-time" you shouldn't be so confident that your theories are correct, because you don't even have a theory for gravity. Don't you get it?

General relativity predicts gravity perfectly from a very small set of axioms.

To me, you're very much like one of those people of the Dark Ages that keeps shouting that the earth is flat.

That's actually a myth, it was common knowledge that the Earth was round since the Greeks proved it scientifically. It's pretty obvious anyway. The Earth casts a round shadow on the moon and a ship's mast falls below the horizon before the body of the ship.

isnt that sort of string theory? according to string theory there are like 12 other dimentions or something.

No.

Parallel universes are not 'other dimensions', although laymen or science fiction films sometimes use that word.

The extra dimensions in string theory are not extra universes, they are extra spacial dimensions; it's completely different.

Originally Posted by Xei

Go on then.

http://www.glafreniere.com/sa_gravity.htm

Now it's your turn. Try to explain gravity except for the three word explanation of "bending of space-time".

What the hell are you talking about now?

Why don't you tell me what 2 + 2 is without saying 4.

The bending of spacetime is what causes gravity. For a more thorough explanation, you will have to complete at least an undergraduate mathematics course.

The person who wrote your beloved website has clearly not studied General Relativity.

Surely, gravity cannot "bend space". It is geometrically impossible.

What on Earth can that mean? It has been shown by experiment that spacetime does bend. This person seems to be living in the 19th century when people thought space was Euclidian.

It has also been shown by experiment that the aether does not exist. Please do not ignore this for the third time.

Originally Posted by Xei

What the hell are you talking about now?

Why don't you tell me what 2 + 2 is without saying 4.

1+1+1+1

The bending of spacetime is what causes gravity. For a more thorough explanation, you will have to complete at least an undergraduate mathematics course.

What causes the bending of space-time? Gravity? LOL. Nice explanation you got there.

Sadly, there is no more to the explanation than this. That's my point.You claim there is, I ask you to show it. You can't, because it simply doesn't exist. I've studied mathematics at university, but I really fail to see any connection at all with the explanation of gravity. Please do enlighten me.

What on Earth can that mean? It has been shown by experiment that spacetime does bend. This person seems to be living in the 19th century when people thought space was Euclidian.

What is space-time? What is it made of? How can it possibly bend? What makes it bend? Time doesn't even exist to start with.

It has also been shown by experiment that the aether does not exist. Please do not ignore this for the third time.

If aether didn't exist, what do light waves travel on then? On nothingness? All waves need a medium to travel on.

What causes the bending of space-time? Gravity? LOL. Nice explanation you got there.

Nice strawman! LOL!

Four-momentum bends spacetime.

Sadly, there is no more to the explanation than this. That's my point.You claim there is, I ask you to show it. You can't, because it simply doesn't exist. I've studied mathematics at university, but I really fail to see any connection at all with the explanation of gravity. Please do enlighten me.

You've studied mathematics at university? What, as part of your sandwich retail course?

You haven't studied general relativity at any rate.

What is space-time? How can it possible bend? Time doesn't even exist to start with.

You're going to have to explain why it's impossible for it to bend.

If aether didn't exist, what do light waves travel on then? On nothingness? All waves need a medium to travel on.

Holy crap...

Aether has been experimentally discounted. Got that yet?? No matter how many vague arguments you try to conjure up, nothing is going to change that fact.

So, what do light waves travel on then? If you know so much about science, it shouldn't be hard to answer this simply question...

Originally Posted by Xei

Four-momentum bends spacetime.

Four-momentum is used for calculation. Not for bending of space-time. LOL

Four-momentum is used for calculation. Not for bending of space-time. LOL

You really don't know what you're talking about, do you?

Four-momentum is a property of objects. Just like mass or velocity. You asked me what property causes spacetime to bend. Four-momentum is the answer.

So, what do light waves travel on then? If you know so much about science, it shouldn't be hard to answer this simply question...

Electromagnetic radiation is self-propogating and has the ability of being able to travel through vacuum.

Photons are the particles responsible for light. Why does a particle need a medium to travel through?

I repeat again; your vague intuitions are of no consequence anyway. Why should your human brain have any sort of ability to cope with these exotic concepts completely outside of biological experience? The plain solid fact that you can't argue away is that there is unambiguous experimental evidence for relativity.

Originally Posted by Xei

You really don't know what you're talking about, do you?

Four-momentum is a property of objects. Just like mass or velocity. You asked me what property causes spacetime to bend. Four-momentum is the answer.

Exactly, it's a property. Not a cause. I never asked for a property, re-read my post.

You claim gravity is caused by bending of space-time. And the bending of space-time is caused by four-momentum? It's lke saying gravity is caused by the diamter of the earth. You can't use a property as an explanation.

Electromagnetic radiation is self-propogating and has the ability of being able to travel through vacuum.

Nope, all waves need a medium to travel on. It's like claiming waterwaves don't need water to travel on. It's like claiming soundwaves don't need air to travel on. On top of that, vacuum doesn't even exist. Just think about it yourself for a few seconds... How can something travel through nothing?

Geezus, I can't stand to read this. Xei, you're wrong. Gravity is the bending of spacetime, but that's caused by a local concentration of mass/energy. Not 4-momentum.

Chayba, the mechanism by which the presence of mass bends spacetime is currently unknown to science. However, the connection between mass and the bending itself has been experimentally verified. If you want to learn more, I suggest you study differential geometry. It's not for laymen.

Also, your notion that waves require a medium is wrong. Maxwell's equations demand that an accelerating charge in a vacuum (or near vacuum) needs to send out a wave of energy. This is simply a matter of mathematics. Pure logic. If you want to refute something, you're going to have to refute Maxwell's equations. Good. Fucking. Luck.

Also, all of your wave examples have had a longitudinal component. Have you ever heard of transverse waves?

It's also already generally accepted in science that vacuum doesn't exist.

Originally Posted by ChaybaChayba

It's also already generally accepted in science that vacuum doesn't exist.

There are many definitions of "vacuum". If you don't want to sound like a complete moron, it would be best to be able to differentiate between them. Maxwell's vacuum refers to a volume of space containing no charged particles or magnets, and few air molecules.

Geezus, I can't stand to read this. Xei, you're wrong. Gravity is the bending of spacetime, but that's caused by a local concentration of mass/energy. Not 4-momentum.

Out of interest, what is your level of education?

You would appear to have at least an undergrad degree in physics or mathematics.

Originally Posted by drewmandan

Geezus, I can't stand to read this. Xei, you're wrong. Gravity is the bending of spacetime, but that's caused by a local concentration of mass/energy. Not 4-momentum.

Chayba, the mechanism by which the presence of mass bends spacetime is currently unknown to science.

LOL! So all this time, Xei was just pulling stuff out of his ass?

Originally Posted by Xei

Out of interest, what is your level of education?

You would appear to have at least an undergrad degree in physics or mathematics.

I'm in 3rd year math, but I'm also studying GR as a fun elective.

Originally Posted by ChaybaChayba

LOL! So all this time, Xei was just pulling stuff out of his ass? Who would've thought!

Actually he was right. It is 4-momentum.

What can I say? I'll know this stuff better by April.

Was that a bad joke? How does a property explain a mechanism?