Physics thread

I don't want to watch the degenerate shitfest Eurovision with my family so here I am.

Ask any physics question I'll do my best to answer!

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What are the odds of time existing?

Pretty high since it's defined as the direction entropy increases and entropy is very real.

I've heard that time is a different dimension, but it's not a spatial dimension.
Why?
To me it makes sense that our movement through the 4th dimension makes us experience time.
That viewpoint also allows for different timelines, which is a nice plus.

Do you think the brain uses quantum fenomena in running consciousness?

Time has a different signature in the metric than space. This is what separates the two. Space has euclidean geometry in that the distance between two points is x^2 + y^2 + … for however many dimensions of space you want.

In special relativity distance between two points in spacetime is t^2 - x^2 - y^2 -… for however many dimensions of space you want.

You can include more dimensions of time if you want too but it will have +ve signature while space has -ve (or vice versa). This is what separates the two.

A more formal way of saying this is that euclidean vectors transform under rotations (orthogonal matricies) which form the group SO(N) in N dimensions. Spacetime vectors transform under SO(M,N) with M dimensions of time and N of space. SO the timelike and spacelike parts form orthogonal subgroups.


No idea. I think the human body uses quantum effects in certain ways tho.

Yeah the euro shitty vision bugs me as well.

Can you explain how black holes emit energy? Cause we only see.. blackness But I heard they somehow can emit energy at the poles? Amirite?

Its still a bit mysterious. You can solve quantum field theory in the vicinity of a BH and show that there is an effective temperature distribution of particles produced but if you actually look at the current of those particles, they don;t move.

Basically all accelerating observers appear to be in a thermal bath due to the Unruh effect.

Why is toast square?

cuz bread is

Why do people think of the Big Bang as pushing the edges of the universe away from its point of origin instead of just flinging a cosmic fuckton of material around?

Inflating a balloon vs a bomb in a warehouse

Because if it were just flinging shit around, you should see stuff older than the big bang around. But we don't see anything older than 14 billion years ago.

Explain this

does baguette make square toast? Checkmate.

How big was the universe before the big bang.

How do we know that those older things didn't become part of the dense ball that had a Big Bang or get flung away by the blast? If Older objects were carried away by the explosion, would light have reflected off of them for us to see?

infinitesimally small.


Suppose the big bang was just a massive supernova. It would be entirely reasonable to think that light emitted from very distant objects before the big bang could reach earth and we could therefore see into a time before the big bang.

Except what we see are very far away stars have the same primordial structure suggesting they were formed after.

Double checkmate, faggot

Thats rectangular you double nigger.

i fucking KNEW u were going to pick on that you ABSOLUTE CUNT but i didnt bother going back to edit it just because you are a finnicky bastard with aspergers syndrome

Wouldn't that primordial light just be picked up as part of the Cosmic Background Radiation?

certainly not. CMB is microwave. Primordial stars are in visible. Big difference.

Interesting, so if I send a clock in an orbit around earth, it is affected. What happens what happens when I send a thermometer?

Not around earth of course, around a BH.

Oh. I thought that the background radiation was just predominantly microwave. Thanks for clearing that up.

Nothing happens around a black hole. You have to be accelerating I.E feel your own weight.

If you fall under gravity you aren't accelerating so to speak. Basically you only measure a temperature distribution if you feel you are accelerating.


The CMB is all microwave. But far away stars are redshifted visible.

Thats it for tonight, will answer questions tomorrow if they are posted.

LISTEN, PLEB
Physics is a pseudoscience. Observation is subjective. Therefore, physics = retardation.
Think about it, and go find a different hobby. It's easy to do. Physics was solved years ago. Thanks for playing.

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That seems like a useless definition.
Entropy is like scrambling a Rubik's cube; if you apply random moves to it, you will almost inevitably go from a solved state to one of many scrambled states. So, watching a movie, you can tell the DIRECTION of time.
But that doesn't tell you what time IS.

When God created the universe, why did he put such difficult math in it?
I think of God as a nerd playing with Mathlab on his Apple.
Seriously God, just make space flat, make everything out of lego, and spare us all this bullshit!

Fresh Dubay!

Can 10 dimensions (or 11)
Exist?

>>>/tumblr/


Not at all. Entropy is defined as heat transfer at a given temperature from one system to another. Thus we can define forward in time as where heat flows from hot to cold and time stopping when heat no longer flows. Its pretty profound!


It's actually not complex. Group theory (at least at the physicist's level) is amazingly easy and nice. It's all about symmetries which nature seems to like.


We only see 3+1 dimensions, but there could be any number, no-one knows.

Yeah, well, scrambling a Rubik's can be defined as color transfer from one side to another.

So if you do random moves we can define time as the direction in which the rubik cube becomes more diverse and multicultural.

The point is that entropy is a great way of defining time. All things feel it so it can be used as a clock. The way a computer works is it looks at a capacitor discharge which is an increase of entropy.

The cube itself has billions of configurations - and it doesn't know which ones are which. From inside it can't see the colours.

So, when you call a cube "solved", you are really saying "This configuration is the one that matters to me - and I applied colored stickers to make it obvious". But it's just one more configuration like the others.

Random moves will take you away from the solved state, for one reason only; because the other states greatly outnumber it.

Moving over to Nature; we can argue by analogy that the atoms don't care how the universe is arranged. They can't see the big picture and they don't know if they're in chaos or order.

We choose one particular state of the Universe (or rather, a group of them) and we call that "ordered" and it's special to us. Entropy drives the universe away from order, simply because the other states greatly outnumber our nice ones.

That's exactly right. It's easy to see and measure which is why it is a good way of defining time.

bump

What did you think about the movie Interstellar?

What is currently floating your boat in science or what would you hope we would ask you about?

Also, is it theoretically possible that a black hole leads to a white hole in another universe?

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