Lord Antares

There is a big misunderstanding between farolero and the rest of the posters. I didn't want to comment on it because of the modnote, but since the discussion continued, I will clarify.

OP is technically right, but also completely wrong in another regard.

What he is trying to say is that a coin toss (as well as white noise) isn't TECHNICALLY RANDOM because it is affected by the physics of how the coin is tossed, at which angles, at what speed etc. He said that if, in two different universes you flipped a coin with exactly the same force, angle etc. you would always get the same result. This is correct. Likewise, white noise is affected by a series of unpredictable circumstances, but not completely random. Of course, this is all greatly unpredictable and therefore as good as random, but he is talking about technicalities.

However, what he fails to realize is that by this logic, there exists no such thing as randomness. Everything happens as a result of something else, and therefore randomness isn't a thing. So by this logic, to answer the question, neither the random.org site or a quantum computer is technically random, but they are so unpredictable that they practically are.

I hope that clarifies it, farolero.

Yes, there is no need to list these as dimensions. Why not count up all the things related to physics you can think of such as energy, mass, singularity etc. and add them to a total of hundereds of dimensions. There is no value in doing that. If there is no explanation of why these would have to be considered as dimensions, then the whole proposition makes no sense.

Also, what do you mean by ''identify them''? You have clearly identified them. If you mean integrate them into physics, then I'm afraid that will never happen as it's not useful or provable in any way.

In thread after thread of a non-science sort, secure in-group members hold forth ad libitem with nothing more beneath their high-wire act than anecdotal experience. And they're typically not called down for failing to present a raft of peer-reviewed data to back up their anecdotes. How about that!?

How is this true at all? I've never seen that happen. I've seen senior members post something that might not have been correct but they were questioned or corrected soon thereafter. If this is so prevalent, at least 1 or 2 examples would be enough.

Also, you may be mistaking the assertions and theories in the speculations forum with genuine questions and misconceptions in the other forums. In the speculations forum, you are required to provide evidence for your claims, since it's supposed to be a place for new theories that have not been formulated.

If that's the case, the senior members are posting replies which are known to be correct and accepted by a majority of the members, not making assumptions of their own. I think this is what you may be misunderstanding.

Municipal piping has been around for over 1000 years. During that time how has physics helped to unclog any drains? When you have a clogged drain do you call for a physicist or a chemist?

Again you completely missed the point. StringJunky specifically said that you would call a plumber to get the clog removed, but you would ask a physicist to explain why it's happening if you are curious about it. A plumber probably wouldn't be eligible to give you a real explanation.

And the OP himself said that he is calling a landlord to get it removed and is asking here in an attempt to understand what's happening, so you had no reason to misunderstand that.

You have an issue with reading and/or understanding the posts.

Yes, that's what I meant when I said

The only way I can reconcile the expansion of the universe with an infinite universe is if the universe itself wasn't expanding, but if matter was simply getting further apart.

But why would this be happening?

 

I meant to say: If his theory were correct then the universe must be infinite.

(Whereas you said "his theory would only be correct if the universe was infinite". This is a logical fallacy called "affirming the consequent".)

I see what you mean. I didn't intend to say that, it was just a wrong choice of wording, I guess.

I would guess I have heard about the same number of people insist it is finite and infinite. The evidence doesn't rule either out.

One thing I really don't understand is how could the universe be infinite and expanding. The only way I can reconcile the expansion of the universe with an infinite universe is if the universe itself wasn't expanding, but if matter was simply getting further apart. But I would be completely baffled as to why this would be happening.

There can be no expansion if Newton is correct. Therefore you can't use expansion to argue against (or for) Newton's ideas.

How so? If there can be no expansion if Newton is correct, then if there is expansion, I car argue against his ideas, surely.

No. Completely wrong.

 

If his theory were correct then the universe must be finite.

But I am only saying this because you said:

Newton demonstrated exactly the opposite: that if his theory were correct, then the universe would have to be infinite.

Stop confusing me. How am I supposed to communicate with you if you keep giving me conflicting information. Maybe you meant something else, but it is not clear to me at all.

 

1. His theory is "wrong".

 

2. What evidence do you have that "most people consider the universe to be finite"?

 

3. As that belief is not based on any evidence it cannot conflict with science.

 

You might as well say that most people's favourite colour is red and this conflicts with the sky being blue. Opinions are not evidence. (Especially when I have no reason to believe that ,most people have this optinion.)

No. That's a ridiculous analogy, especially because you misunderstood what I was trying to say. But it is irrelevant, since you are now saying that his theory is wrong.

The only thing that you are right about is that I don't have evidence for point number 2. I spoke from experience; I've heard/read that the universe is finite more times than not, but that is not evidence.

If there is no mechanism, then that changes the perspective a lot. The expansion would negate this notion of everything falling towards the center of mass, I would think.

So Newton could be wrong, right?

I know it doesn't matter what people think. I was trying to make the following point:

you said his theory would only be correct if the universe was infinite. Most people consider his theory to be correct. Most people consider the universe to be finite. That is a contradiction.

There is mechanism for an expanding universe in Newton's theory

I assume you mean to say that even with the expansion of the universe, everything would still gravitate towards the center of mass if the universe was finite. (according to Newton).

But as far as I understand it, more people think the universe is finite than infinite but we all consider his theory to be true. So how does that work?

Any chess players out there? Any officially rated? Titled?

Anyone wants to play in between ourselves?

Discuss tournaments, news, etc.

This is the general chess thread.

I had the same exact problem this year as well as last year.

I have solved it, though. Buy a dehumidifier.

After you are done taking a shower, turn it on immediately and open the window. It should absorb the moisture before it does damage.

If not, then there would be a centre of mass that everything would fall towards.

Yes, but this was before he knew that the universe is expanding. Doesn't this not hold true with this knowledge?

If the universe is infinite, then the pull in all directions basically cancels out.

I see. This is what Bender was trying to say as well, I believe. But this is true only with the assumption that there is an infinite amount of matter, as well as space. Because if there was a finite amount of matter in an infinite space, it would still fall towards the centre of mass, right?

This is a result of not being familiar with correct terminology and having to resort to linguistic elaborations.

It does not mean I am talking nonsense.

No, I guess my terminology is incorrect. I meant to say overall force on all of the universe. Following Newton's equation, a finite amount of mass would have to exert an infinite amount of gravitational force.

EDIT: @Bender - your point two is interesting, I was actually wondering if this could be true, but this equation proves that it can. It would make sense in this case as well.

No, I'm sorry, that was incorrect. It doesn't invalidate Newton's law but it means that every objects exerts an infinite value of graviational force.

As distance increases, gravitational force fades but some value, however small, is still present. Therefore, there is an infinite value of net gravitational force of any object for an infinite universe. As it directly depends on the mass of the object, that means that we get to infinitesimal values approaching infinity, no?

My understanding of what you wrote is that you don't realise that gravitationally-bound objects stay that way.

That is not true at all, it's a strawman argument. I was simply assuming that it weakens very slightly, not that it completely overcomes the gravitational force.

Also, you will note that this thread is a simple question from someone who is not so knowledgeable towards the people who are. It is not a theory or assertion of any kind.

/cut

Thank you. Of course I have misunderstandings of my own but I did not want to give up on the answer simply because my question was misunderstood.

What you wrote is what I was saying, but I made the blunder of thinking that space was physical. And so if it was, Newton's law wouldn't hold true for space because in the process of expanding and distributing the gravitational force equally, it would have to be weakened in te same distance as before expansion. That was my whole point. But space isn't physical nor does it have mass, so it doesn't have to follow this logic.

Which brings me to another question: If Newton's law is true, then space can't be infinite, right?

. In GR, it's not a force. So it can't require more force in a larger universe.

Yes, you are correct. This got me into a very lengthy train of thought and I had some interesting questions and conundrums. However, they would be too long to post and would take too much effort from you to explain so I refrained from posting. What I will ask, though, is this:

I was going to draw a ball on two different cloths which are held by the edges. The ball would curve the smaller cloth more and the bigger cloth less because it would have to disperse the same amount of gravitational force on a bigger area. But this cannot work for space because it would invalidate Newton's law. So my question is why does it work for a ball and a cloth, and not a planet and space if the same force is involved? What is the difference? I realize that it is not technically a force so, numerically, it wouldn't have to provide more force for a larger universe as you correctly pointed out, but the principle is still very similar.

Is it because space is massless and the cloth is not? That would make sense.

It seems to me that he doesn't understand that gravity overwhelms the expansion where it is sufficiently strong.

Nowhere in my posts did I imply the contrary. Explain how you deduced that.

The speed of lights moves at a certain speed, however large. So of course it will be seen sooner by someone who is closer to the lightning bolt. Of course, this difference is imperceptable by humans and they would both agree to seeing it at the same time, but we are talking about technicalities, right?

Maybe I'm missing something because you haven't provided the video. There's not enough info to discuss more.

And, you could argue that the curvature of spacetime could only be measured by using a second mass.

Not neccessarily. Shining a beam of light would do.

I will draw some illustrations and post them later in the evening.

Yes, but the object that accelerates on earth (such as a human) is also a mass. This acceleration wouldn't mean anything if there wasn't a mass to accelerate.

I think I thought of an example to illustrate my question, seeing how it doesn't seem to be clear enough. I will post it a bit later, since I have to go now.

 

 

You can talk of the gravitational field of a single mass with Newtonian physics.

 

No. It's always going to be GMm/r^2. If m and r are the same for the remote object, the force is the same. There is no "dilution" from having more volume, or by introducing a new object.

But does it imply that the gravitational filed does exert force even if there isn't another mass nearby? I thought it was just a field in which gravity would act in such and such way IF there was another mass.

Also, can you answer post #5? I know you are very knowledgeable but both you and Mordred, I think, missed what I was getting at.

I know this but isn't there another difference?
In Newtionian physics, gravity strictly needs to be btween at least two masses.

In general relativity, one mass is enough to create distortion of spacetime, no?

Yes but it degrades by a certain value in a certain amount of time. In 0 seconds, it does not degrade at all. Raise the time limit linearly and it degrades proportionally to the time increased.

So the question doesn't really make sense.

I said that it has no effect on Newton's law and that it holds true. The attraction of TWO masses will change if they get further apart as a result of the expansion of the universe, but that is in unison with Newton's law because r has increased between the two.

I am saying that, as the universe expands, the force of gravitation of a mass has more and more reach every second. Simply put, it has more of the universe to cover. As the gravitational force is proportional to the mass of an object, and therefore limited by it, does that mean than it is constantly weakening as it needs to exert the same amount of force to a larger area? Or is the mass of everything increasing? This is what I'm asking.

OR are you saying that there need not be an increase in gravitational force for a larger space because it takes no force to bend space, only to pull objects together?

EDIT: It presents no questions to Newton's law so don't look there. It presents questions to general relativity.

Newton's law of universal gravitation states that F= g (m1 x m2)/r², i.e. a particle attracts every other particle in the universe with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. In Newton's view, there need to be two masses present for gravitation to take effect.

It has been proven by general relativity that gravitation occurs with just one mass present, as it is not a force which acts upon objects per se, but rather on the space in between them. This all makes sense and Newton's law still holds true, as any two masses will behave in accordance to his equation.

However, I have just one problem with Einstein's depiction of gravity. (problem as in ''I don't understand it'', not as in ''I'm trying to refute it'', to be clear).

If it is true that Newton's inverse square law extends indefinitely and the universe is constantly expanding, then one of the two statements must be true:

1) The gravitational force of every object is weakening, because it needs to extend the same amount of force over a larger area. The overall amount of gravitational force exerted by a mass stays the same, but is decreased within any given distance.

2) The mass of every object grows proportionally to the rate of expansion of the universe. This is the only way an object could exert the same amount of force over a distance, but is bizzare to consider.

These are the only two options I can think of. Neither of these would refute Newton's law in reality, because as the universe expands, the objects get further and further apart, and so the weakening in gravitational attraction would simply be explained by the increase in r.

Actually, I am not sure how the second case would affect Newton's law. I am trying to think about it, but this option is far-fetched anyway.

This problem only occurs when you talk about general relativity's concept of gravity. What do you think about this? What am I missing here?

All replies are appreciated.