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Comment Isn't this a kind of proof that gravity is push? (Score 3, Interesting) 149

I think space itself is some kind of medium and not necessarily matter based. Currently, its composition is unknown. You can call this medium aether if you like, just do not confuse it with the luminiferous aether. There are several aether theories out there, one of the popular ones is the Superfluid Vacuum Theory.

Now, back to gravity. We know since Einstein that matter curves/disturbs space**. So, this medium, which is disturbed by matter, wants to be 'smooth' and it exerts a force on matter. This force is obviously a push force and we call it gravity.

From our perspective there is no way to differentiate between pull or push. Maybe until now.

** I know that according to GR gravity is a curvature of space-time and not just space. But if space itself is some kind of medium then the time dimension simply does not exist. What happens is that the disturbance of space prevents matter particles to interact with each other. We perceive this lack of interaction as if 'time' slow down since there is no change (We can only perceive 'time' by observing change). This picture is compatible with GR since relativity between moving bodies through space remains. However, it establishes a distinguished reference frame which is space itself.

Comment Re:Hilarious (Score 1) 470

Well, they debunked the luminiferous ether, but there are other aether theories out there. A 'popular' one is the Superfluid vacuum theory.

https://en.wikipedia.org/wiki/...

Also, Erik Verlinde talks about 'elastic back pressure' in his recent paper https://arxiv.org/pdf/1611.022... concerning 'emergent gravity'.

Personally I do not think gravity is emergent, but I wonder if elasticity could be applied to space itself. That could explain observations without dark matter.

Even dark energy can be explained. In this case dark energy would be the elastic energy of space. So, it's no wonder the universe is expanding.

It has also implications to the fate of the universe. I mean it may not depend on how much matter is in the universe, but rather what kind of properties space has.

Comment Space can be elastic (Score 3, Informative) 164

It's strange that Verlinde uses 'elastic' in the abstract.

"The emergent laws of gravity contain an additional dark gravitational
force describing the elastic response due to the entropy displacement."

I think space can be thought of like some kind of elastic material. At first, space begins to regain its original form (where there is no matter) quickly from the center of gravitation. However, as we go further and further from the center this process slows down.

The end result is that space will be more curved than we expect at large distances.

Comment UBI will be a disaster (Score 5, Interesting) 426

The complete naivete of the slahdot crowd concerning UBI is beyond comprehension.

It looks like most slahdotters think a simple tinkering with the taxation system (which will mostly affect wealthy corporations and individuals) will bring universal joy to everyone.

I tell you what. It will absolutely do no good. It looks like everyone thinks that wealthy men keep their wealth in some kind of vault like Smaug. This is not the case. Most of their wealth is already in the economy, there is basically nothing you can get from the wealthy by taxing them more.

At best UBI will create a society similar to the one in Atlas Shrugged. I do not like to live in such society.

So, what is the solution to the problems UBI is supposed to cure? Most probably the answer is WAR. Currently, nobody dares to comprehend this possibility.

Comment There is no time dimension (Score 1) 268

http://phys.org/news/2011-04-s...

I think until the majority of scientists do not accept this we won't have a unified theory.

Even Lee Smolin acknowledges that we have some problem with time (in The Trouble with Physics), but he thinks the problem is that we treat time as a static/frozen thing while he thinks it is a dynamic thing like space itself (eg. the shape of space continuously changes due to matter).

Comment Possible if the Universe is non-local (Score 1) 238

There are some theories, most prominently the De Broglie-Bohm theory (https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory) which assume that the Universe itself is inherently non-local.

These theories are basically Aether theories (https://en.wikipedia.org/wiki/Aether_theories) which assume some kind of unknown medium (possible that medium is space itself). Do not confuse these with the Luminiferous aether theory.

If there is such medium that can explain a lot of things eg. why the Universe appears to be the same in all directions, etc. This was explained before with the Inflation theory, but that one bit the dust (http://www.space.com/28423-cosmic-inflation-signal-space-dust.html).

Comment Re:Enigma (Score 1) 128

Obviously, you do not understand how enigma works. With 20 wheels you have an 26^20 initial configuration and defining thousands of wheel turning patters makes the attacker's work much-much harder.

And actually, cracking the original enigma should takes just a few seconds on today's desktop computers.

Enigma basically replaces each letter with a different one according to the wheel settings. With 20 wheels the initial configuration contains 20 characters plus the number of the wheel turning pattern. This is far stronger than a simple one-time pad with 20 characters (aka 20*5 bits = 100 bits).

Also, a wheel can contain the whole ASCII table in which case the initial configuration is 255^20.

Comment Enigma (Score 2) 128

Just create a software version of Enigma (https://en.wikipedia.org/wiki/Enigma_machine) with eg. 20 wheels. Also, create a matrix which contains how the wheels should turn. You can create thousands of wheel turning patters. Voila, unbreakable encryption without using a sufficiently long one time pad.

Of course, the initial configuration has to be sent somehow (eg. via courier or other conventional ways which 3-letter agencies seem to forget) and the encoding/decoding machine should never be connected to the internet.

Comment Re:TL;DR (Score 1) 189

No, I invoked the gambler's fallacy because it seemed to me that the original poster assumed that the system has memory.

It is stated in wikipedia:
Gambler's fallacy does not apply when the probability of different events is not independent...

Since I consider different rocket launch as independent events I think gambler's fallacy applies to some extent.

So, the only way to calculate a success rate of a launch if you get the failure rate of every component of the rocket and do some calculations based on those. However, calculating the success of the 9th mission after the success of the previous 8 or before even the first one has no physical meaning. Maybe it has some kind of theoretical one which has no connection to the physical world.

Comment Re:TL;DR (Score 1) 189

>We have no missions. What is the chance that we get 9 missions coming back alive? (1/2)^9 = 0.001953125 = 0.2%.

This is true if you have a fair coin as in the Gambler's fallacy example. However, I do not believe a rocket can be treated as a fair coin. First of all you have to change the coin for every toss and these coins have to be imperfect. This will totally screw up a simple probability calculation.

In reality, if you go down to the quantum level you can say that the quantum state of each rocket will be totally different and in this way calculating the probability of the 9th mission before the first one will have absolutely no meaning.

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