[ExI] Dark energy = (anti)gravity?

Wed Oct 4 17:04:22 UTC 2017

On Mon, Oct 2, 2017 at 3:21 AM, Stuart LaForge <avant at sollegro.com> wrote:

> >> A single state with no other states to compare it to has zero
>>>  
>>> energy and entropy.
>>
>>

> I would
>>  
>> say in that situation energy and entropy would be undefined not zero.  
>
>
> The entropy of a state with a probability of 1 is ln(1)
>  
> or precisely zero
>  
> in both Boltzmann and Shannon formulations. I didn't know this was even
>  
> controversial.

Entropy is proportional to the logarithm of the number of 
ways previous micro-states could have produced the present macro-state,
but if at the start of time the universe was in one state there were no
previous
micro-states
, or previous anything.

> 
> if the universe has a single age that all observers can agree upon,
>

But they don't agree, some observers will say the universe is older than
others.

> > 
> then there must be a universal proper time from which time-symmetry could
> be introduced.

There is no universal time everybody can agree on. If a traveling observer
goes from point A to point B the
Proper T
ime
of that 
 journey is the time measured by the observers own stopwatch and using the
traveling observer's definition of simultaneity to decide when to start and
stop the stopwatch. But there is no universal agreement, some observers
will say the stopwatch is running too slow, others will say it is too fast,
and they will say the traveling observer started and stopped the watch at
the wrong time.

>
> 
> So Noether's theorem and Einstein's equations could both be satisfied
> given the correct boundary conditions.
>

Noether's theorem says that if the laws of physics tell a system to behave
in a certain way at one time and the system behaves the same way at any
other time then energy is conserved, but it won't behave the same way at a
different time because spacetime is accelerating.

> >
>> >
>> consider all the photons in interstellar space, as
>>  
>> space expands with time the number of photons remains the same but
>> each individual photon is redshifted and thus has less energy than it did
>> before.
>
>
> > 
> Yes but in that process the particles that emitted those photons and the
> particles that absorbed of those photons would have gained a proportionate
> amount of kinetic energy relative to one another by way of their relative
> Hubble velocities. The energy lost by the photon should be gained by its
> terminal particles.
>

We call it  Cosmic 

Microwave Radiation but when those photons were created 380,000 years
after the Big Bang they were not microwave photons they were visible light
photons but due to the expansion of the universe they have been stretched
out into far less energetic microwave photons.  The ancient particles that
emitted those photons emitted light, the modern particles that absorb those
same photons absorb microwaves, the energy in those 2 things are not equal.

> 
> the curvature of the universe as a whole has been bounded to be
> within +/- 0.004 which causes the flatness problem. The FLRW metric
> implies that if the universe has so little curvature now, in the beginning
> it would have to have had way less curvature, on the order of 10^−62. That
> is so infintesimally small that the probability of such an arrangement so
> close to zero, without actually being zero, is vanishingly small.
>

I don't know how you could even assign a probability to something like
that.
If the universe is infinitely large and negatively curved you'd expect the
local curvature to be 
vanishingly small
. Even if the universe is finite the local curvature would still be
unmeasurably small if the universe were big enough. But is the universe big
enough? I can't even make a guess about that.

> 
> And in a flat universe, GR conserves total energy at least according to
> the Friedmann equations and my potential field equations.

If 
spacetime
 is not evolving then energy is conserved, but we now know something
Friedmann did not ; spacetime is evolving, not only is it expanding it's
accelerating. 

From  Sean Carroll at:
 http://www.preposterousuniverse.com/blog/2010/02/22/energy-
is-not-conserved/

*"It’s clear that cosmologists have not done a very good job of spreading
the word about something that’s been well-understood since at least the
1920’s: energy is not conserved in general relativity."*

> >
> 
> as the density approaches an assymptote at located at twice thecritical
> density

Dc = 3H^2/(8*pi*G),

The equation is correct but keep in mind 
H, the Hubble parameter
,
is not a constant
but is
decreasing with time. And the value of Dc is not just determined by the
mass of matter in a unit of space, pressure and tension are also part of
it.

>
>> >
>> The energy required is not the issue,  gravity
>>  
>> waves don't travel faster than light, and sending messages into the past
>>  
>> creates logical contradictions. Even quantum entanglement  won't let
>> you communicate faster than light. 
>
>
> > 
> Here you are trying to eat your cake and have it too.
> 
> You say that quantum
>  
> entanglement doesn't allow "me" to communicate FTL but the particles
>  
> themselves MUST comunicate FTL ergo the meaning of non-local.

No, communicating is not the same thing as influencing, communicating
involves transferring Shannon style information and

entanglement

can't do that faster than light. But it will still let you influence things
faster than light.

You and I have quantum entangled coins, I'm on Earth and you're in the
Andromeda Galaxy 2 million light years away.  I flip my coin 100 times and
record my sequences of heads and tails and then just one hour later you do
the same thing. We both think our sequences look completely random as they
pass all known tests for randomness. You then get into your spaceship that
moves at 99.9% the speed of light and visit me. After 2 million years you
arrive on Earth and we  compare the notes we took on our two sequences and
find that all 100 flips are identical. Clearly my coin influenced your coin
2 million light years away and did so in just one hour, but there is no way
I can  use that to send a message. All it does is change one apparently
random sequence to another apparently random sequence, the fact that there
is something funny going on and things aren't as random as they appear can
only be discovered when the 2 sequences are placed side by side, and that
can only be done at the speed of light or less.

>
> 
> The universe's "internal memos" are either FTL and off-limits to us or
> they  are not. You can't have it both ways.
>

We don't have it both ways, it's off limits to us period.

>
> 
> My point is that you *can't* use it to send messages into the past. Only
> the universe can. It's like a private communications channel between
> particles to exchange quantum information like position and momentum.
>

OK that might be true, it sounds rather like John Cramer's transactional
interpretation of quantum mechanics; but I have to say backward causality
makes me nervous even though

nothing

Shannon

would recognize as information is sent into the past and so
no 
paradoxes

are

produced.

>
> > 
> Let me put it another way. How is the mass of a black hole distributed? Is
>  
> it spread out all over the event horizon?

Nobody knows. General Relativity says all it's mass is concentrated at a
mathematical point at the center that has infinite density but that is
probably wrong because it doesn't take quantum mechanics into account and
in physics if your equation produces infinity in something it's reaching
the limit of its usefulness and it's time to start looking for a new
equation. But externally it doesn't matter, the gravitational field would
be identical if all the mass were at the center or if all the mass were
distributed evenly over the event horizon surface.   

> 
> Damn, I wish LIGO would catch a binary neutron star merger with optical
>  
> back up already.
>

It may have already done so, the LIGO people can be pretty secretive. The
next few months should be interesting.

> > 
> I know it is unintuitive that gravity could be both an attractive and a
> repulsive force based on density rather than something like charge.
>

Einstein says density isn't the only thing that makes a gravitational
field, pressure and tension do too, and tension (negative pressure) makes
gravity repulsive if the tension is strong enough. And

Dark Energy isn't made of matter so it doesn't become less dense as space
expands instead it is a property of space itself
,
so the density of Dark Energy remains constant regardless of how much space
expands. Because Dark energy is persistent it gives a constant push to the
universe, and if you push on something with a constant force it will
accelerate.

> > 
> BTW, as a testable prediction my theory predicts that objects inside an
>  
> evacuated hollow spherical shell at zero G, should very slowly gravitate
>  t
> o the closest part of the hollow sphere unless they were in the exact
>  
> center.
>  
> This is in direct contradiction to what Newton's shell theorem predicts by
>  
> purely attractive gravity.

It seems to me that is pretty good evidence your theory must be wrong.

A simple corollary to

Newton's shell theory

states that externally the sun's gravitational field behave
s
as if all it's mass were concentrated at it's center point, if this were
not true the orbits of the planets would be quite different from what we
have observed and would have been noticed centuries ago.

 John K Clark
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