
One-electron universe - agentzebra
https://en.wikipedia.org/wiki/One-electron_universe
======
Steuard
Physics professor here. As others have said, this is a really cute idea in
physics that touches on some neat properties of the universe (like
fundamentally identical particles, conservation of lepton number, and the
effects of time reversal on particle properties), but:

1\. It's more akin to philosophy than to science: this suggestion either has
no testable consequences (or if it does, its predictions look obviously false:
see below).

2\. In all of our observations of the universe there seem to be many more
electrons than anti-electrons, but this concept would seem to imply that the
number should be exactly equal. You can try to get around that, but anything
you do is a stretch.[1]

3\. The formalism of quantum field theory naturally includes plenty of
situations where electrons and anti-electrons form "closed loops" in time.
(The classic example is a something like a photon giving rise to a virtual
e-/e+ pair that immediately annihilates back into a photon, but they can get a
lot more complicated.) Those closed loops would not be connected to the
hypothesized "one electron" bouncing back and forth through all of time, so
this idea would fail to explain why they also look identical to the rest.

So in my book, the beauty of this idea lies entirely in the fact that it could
be suggested at all. It doesn't actually match reality, but it does give some
striking intuition about how particle physics works.

[1] You could suggest that there is some other (unobservably distant?) region
of the universe where antimatter dominates, but there's absolutely no evidence
to support that suggestion. As another idea, the quote in the link suggests
that "maybe the extra anti-electrons are hiding in the protons or something".
But anything of the sort would seem to eliminate the whole point of saying
"it's all one electron" (which always has the same properties, etc.).

~~~
VladRussian2
> a photon giving rise to a virtual e-/e+ pair that immediately annihilates
> back into a photon

i'm been wondering about validity of virtual particle trick - while it is
preserves charge, etc... doesn't it violates entropy principle of the 2nd law,
ie. a pair of e-/e+ seems to have less entropy than the original/resulting
photon, thus e-/e+ always happy to produce a photon, while photon would never
produce e-/e+ pair without "help".

~~~
Steuard
The glib answer here is that there's really no such thing as the 2nd law when
you're talking about a small number of individual fundamental particles. The
statement "entropy never decreases" is actually a purely statistical claim,
and it only rises to its usual level of essentially unbreakable validity when
you're dealing with macroscopic numbers of particles (the number 10^23 gets
thrown around a lot, though it becomes an awfully compelling "law" even with
just a few hundred particles in the mix).

But as for your actual example, it's important to distinguish between
_virtual_ pair production and longer-lived pair production. A single photon
can momentarily "decay" into an e-/e+ pair which then annihilates back into a
photon, and in fact quantum field theory tells us that this sort of process is
an intrinsic part of how photons travel through space. (Similar things happen
for all other particles as well.) But conservation of energy and momentum
during this process leads to weird effects like violations of the usual
mass/energy/momentum relation of relativity, which is essentially why we call
the e-/e+ "virtual" particles (or "off-shell"[1]).

For a "real" annihilation between an electron and a positron, you'll always
wind up with two photons in the final state (necessary to conserve momentum
and energy). By the same token, to produce an e-/e+ pair you'd need two
photons, not just one, and those photons would need to have enough energy to
provide the mass of both particles _and_ enough kinetic energy to satisfy
momentum conservation. I wouldn't invoke the 2nd law here (as I said above),
but the point you're making is still valid: because so much of the e-/e+
energy is "used up" in their mass, there is less "phase space" available
(fewer possible momentum states) in that configuration than as two photons, so
the probability of winding up in that state is correspondingly lower. (Also,
an electron and positron are electrically attracted to each other and will
naturally tend to meet up to annihilate, but two photons have no such
tendency.)

I'm not sure that any of that was interesting or useful, but there you go.

[1]
[https://en.wikipedia.org/wiki/On_shell_and_off_shell](https://en.wikipedia.org/wiki/On_shell_and_off_shell)

~~~
VladRussian2
>The glib answer here is that there's really no such thing as the 2nd law when
you're talking about a small number of individual fundamental particles. The
statement "entropy never decreases" is actually a purely statistical claim,
and it only rises to its usual level of essentially unbreakable validity when
you're dealing with macroscopic numbers of particles

All the fundamental laws of physics, including the Schrodinger equation follow
the 2nd law, so it is somewhat

~~~
VladRussian2
sorry, somehow partial text got submitted.

>The glib answer here is that there's really no such thing as the 2nd law when
you're talking about a small number of individual fundamental particles. The
statement "entropy never decreases" is actually a purely statistical claim,
and it only rises to its usual level of essentially unbreakable validity when
you're dealing with macroscopic numbers of particles

All the fundamental laws of physics, including the Schrodinger equation,
follow the 2nd law or in other words they describe application of 2nd law to
the given area of physics, i.e. they express "entropy never decreases"
principle in terms of the objects of that physical area.

>"there is less "phase space" available (fewer possible momentum states)"

ie. less entropy :)

>an electron and positron are electrically attracted to each other and will
naturally tend to meet up to annihilate

2 particles having negative and positive charges - less entropy than the
entropy of 2 resulting neutral particles. Attraction (getting closer -
increasing entropy) and annihilation (erasing the charge difference -
increasing entropy) are in full compliance with, and i'd say direct
manifestation of, the 2nd law :)

~~~
Steuard
My glib objection was not to the notion of there being less entropy in one
state than the other, but in calling the result "the 2nd law of
thermodynamics" in cases like this.

The phase space argument means that it is _less likely_ for the system to wind
up in the e-/e+ state than in the 2-photon state, and calling that a
manifestation of entropy is entirely sensible. But in general, there's a non-
negligible chance that the system will wind up in the e-/e+ state anyway: it's
very much a possibility (and becomes even more so when the total energy is
greater).

I usually reserve the term "2nd law" for cases where the probabilities are
tiny enough that it's essentially impossible for the entropy to decrease by
any remotely significant amount. That level of certainty typically requires
systems of many particles, not just one.

~~~
VladRussian2
this is why i drop "of thermodynamics" because that calls for many-particles
situation. Referring to "2nd law" i mean the generic "non-decreasing" entropy
principle, and i'm wondering about its violations - mainly i believe that
there are no violations of it in the physical world (as the known laws of
physics seems to obey/describe that principle), and this is what prompted my
original question about virtual particles.

I understand that pure statistical interpretation allows for non-negligible
chances of the violations. What i'm wondering about is whether strong, non-
statistical, interpretation is valid - ie. whether anything looking like a
violation is just a non-complete calculation. After all it is pretty
fascinating that entropy principle applicable (at least in statistical
interpretation) on all scales - from the whole Universe down to quantum
systems and for all the physical laws/forces.

~~~
Steuard
I guess that I have trouble imagining how any law of physics that I know of
would enforce such a rule. The whole point of statmech is that the 2nd law is
an emergent phenomenon: it's not a separate influence on the universe
independent of the known fundamental forces, but rather a consequence of how
those known laws play out in cases with many particles and/or states. What
you're suggesting is some _additional_ influence at microscopic scales, and
that seems quite implausible to me. (Just how strict are you imagining this
rule would be? If two states had phase space volumes in a 51/49 ratio, are you
suggesting that the system would _always_ pick the 51?)

It's hard to list intuitive counterexamples to your suggestion here, since
anything intuitive is by definition part of a macroscopic system that would
obey the 2nd law anyway. But... for instance, are you saying that you don't
believe in the Maxwell speed distribution in an ideal gas? If no molecular
interaction could ever take a system from a larger to a smaller total phase
space, then every molecule in an ideal gas should eventually converge to the
RMS speed. That's a clear experimental prediction, and I'm pretty sure that
the usual answer has been well-tested (both explicitly and implicitly).

------
51Cards
If that's the case then I have to talk to my electric company about charging
me over and over for the same re-used electron.

~~~
jacquesm
You can talk to them anyway since they're using AC which means they're pumping
the same electrons around over and over again. Whether it's just one or a
couple that they re-use who cares, the fraud is obvious.

~~~
oleganza
Some electrons are leaking into the ground under your apartment. You should
pay at least for those.

~~~
dfritsch
Wouldn't that just be the one electron also leaking into the ground?

~~~
dj_axl
You have to pay for the one electron. Since it's the only electron, the cost
is infinite. This results in a buffer overflow. Your utility bill is an
overflowed unsigned short, divided by 100. This is why the maximum utility
bill you will ever see is $655.35.

------
ISL
If you enjoyed that notion, you'll probably like this one too:

[http://en.wikipedia.org/wiki/Magnetic_monopole#Dirac.27s_qua...](http://en.wikipedia.org/wiki/Magnetic_monopole#Dirac.27s_quantization)

~~~
drjesusphd
I'll see your Mangetic Monopole, and raise you a Boltzmann Brain.

[http://en.wikipedia.org/wiki/Boltzmann_brain](http://en.wikipedia.org/wiki/Boltzmann_brain)

~~~
chegra
I will see your Boltzmann brain, and raise you Infinite monkey Theorem.

[http://en.wikipedia.org/wiki/Infinite_monkey_theorem](http://en.wikipedia.org/wiki/Infinite_monkey_theorem)

~~~
mratzloff
_In 2003, lecturers and students from the University of Plymouth MediaLab Arts
course used a £2,000 grant from the Arts Council to study the literary output
of real monkeys. They left a computer keyboard in the enclosure of six Celebes
Crested Macaques in Paignton Zoo in Devon in England for a month, with a radio
link to broadcast the results on a website.

Not only did the monkeys produce nothing but five pages consisting largely of
the letter S, the lead male began by bashing the keyboard with a stone, and
the monkeys continued by urinating and defecating on it._

~~~
nkurz
Wild! The original seems down, but archive.org has copies:
[http://web.archive.org/web/20031203230517/http://www.vivaria...](http://web.archive.org/web/20031203230517/http://www.vivaria.net/experiments/notes/publication/)

------
unclebucknasty
Well, this could explain the EPR Paradox[1]:

 _It is one thing to say that physical measurement of the first particle 's
momentum affects uncertainty in its own position, but to say that measuring
the first particle's momentum affects the uncertainty in the position of the
other is another thing altogether. Einstein, Podolsky and Rosen asked how can
the second particle "know" to have precisely defined momentum but uncertain
position? Since this implies that one particle is communicating with the other
instantaneously across space, i.e. faster than light, this is the
"paradox"._[2]

The answer: It's the same electron being measured! No more paradox.

[1]
[http://en.wikipedia.org/wiki/EPR_paradox](http://en.wikipedia.org/wiki/EPR_paradox)

[2]
[http://en.wikipedia.org/wiki/EPR_paradox#Einstein.27s_opposi...](http://en.wikipedia.org/wiki/EPR_paradox#Einstein.27s_oppositionition)

~~~
wetmore
That solution doesn't work in the general case. Say I have an anti-correlated
EPR pair of electrons, such that measuring spin-up for one particle means I
will subsequently measure spin-down for the other. Then your solution doesn't
work.

Also the EPR paradox applies to quantum states that are not necessarily
electrons.

FWIW the EPR paradox is no longer a paradox anyway since you cannot use
entanglement to transmit information faster than the speed of light, therefore
preserving locality. The reason Einstein et al. termed it a paradox was
because they thought it represented some sort of instantaneous information
transfer.

~~~
_dark_matter_
You are mostly correct, except for the last part. EPR denied that it was
faster than light transfer, but instead thought that the information was
already present in the second particle, thus implying that the theory was
incomplete. This was also more exciting since it left open an avenue for
further development in physics.

~~~
unclebucknasty
Right. Either relativity or our understanding of quantum mechanics had to be
"violated" in order to explain their observations. Einstein & Co. chose the
latter with their idea of hidden parameters (i.e. information already present
in the second particle).

But, later experiments based on Bell's theorem seriously challenged the hidden
parameter explanation, preserving quantum mechanics in the process.

So, that takes us back to instantaneous information transfer _or_ a third
option: one electron (or any particle for that matter)!

------
colanderman
Don't forget, this explains pair production too!
([https://en.wikipedia.org/wiki/Pair_production](https://en.wikipedia.org/wiki/Pair_production))
Pair production nuclei are just the places the electron decided to make a
U-turn :)

------
ck2
That makes no sense to me, I mean what about particle colliders that bash
together electrons to get subatomic particles.

That would mean you are colliding the sole electron with itself?

What about electrons on the opposite sides of a planet or even universe, they
are violating the speed of light without any gain in mass if it's a single
entity.

How about when an electron falls into a blackhole, why aren't all the other
"copies" affected by the dramatic space-time shift of such an event?

~~~
sherjilozair
If you use a time machine now, and travel to the past, you can collide with
the past yourself, right? :)

~~~
ck2
If you damage an earlier copy of yourself, your later version should also
reflect the damage?

Unless we are dealing with an infinite-outcomes model where there are no
paradoxes.

~~~
stan_rogers
"One of the major problems encountered in time travel is not that of
accidentally becoming your own father or mother. There is no problem involved
in becoming your own father or mother that a broadminded and well-adjusted
family can't cope with. There is also no problem about changing the course of
history - the course of history does not change because it all fits together
like a jigsaw. All the important changes have happened before the things they
were supposed to change and it all sorts itself out in the end." \-- Douglas
Adams

------
ultramundane828
That reads more like a bad, wordy, science joke than an actual hypothesis to
me.

~~~
adambard
It's more of a scientific koan. Interesting to consider, but of little
practical consequence (unless, of course, the missing positrons could be
located).

------
mr12
This idea is very, very old. I first read about it in the book Stalking the
Wild Pendulum.

[http://www.amazon.com/Stalking-Wild-Pendulum-Mechanics-
Consc...](http://www.amazon.com/Stalking-Wild-Pendulum-Mechanics-
Consciousness/dp/0892812028/ref=sr_1_1?ie=UTF8&qid=1380136812&sr=8-1&keywords=stalking+the+wild+pendulum)

~~~
shardling
Why are you referring to a book that was published well after the quote in the
article?

>"Feynman's thesis advisor, John Wheeler, proposed the hypothesis in a
telephone call to Feynman in the spring of 1940"

~~~
mr12
Because I'm lazy and didn't read the entire article. You got me.

------
gesman
Here's the best explanation of it from Bashar:
[http://www.youtube.com/watch?v=VNxnE8nXFo4](http://www.youtube.com/watch?v=VNxnE8nXFo4)

Search google for "bashar prime radiant"

------
protez
If it would ever make any sense, multiple electrons should weigh no more than
one single electron. But that would be obviously false under Standard Model,
to treat something singular to be that apparently multiple. Or, our present
physics needs to totally reconstructed to incorporate that, by building
everything again from defining the "tremendous knot" and the implications from
its hypothetical world lines. Instead, what if, everything from electrons,
protons, even strings, is sort of that "knot?" That would make more sense, in
terms of coherence.

------
teilo
"Maybe they are hidden in the protons or something." Priceless.

------
drjesusphd
If this were true, there would be much more antimatter in the universe than is
currently observed.

The idea is that since positrons can be viewed as electrons moving backwards
in time, it may be the same electron weaving its way to the future and past
countless times. But that would imply that the number of electrons in the
universe = the number of positrons.

~~~
mratzloff
> _But that would imply that the number of electrons in the universe = the
> number of positrons._

Hence Feynman's objection.

------
znowi
I suspect if this idea was not coming from Wheeler/Feynman, it would be
readily dismissed as a crackpot theory :)

------
GuiA
This seems like it would be a major discovery if proven true.

Unlike many similar theories though, the people behind this have enough
scientific credentials to make it maybe plausible?

So why is the article so short? Has there been any additional research?

~~~
JonnieCache
_> So why is the article so short? Has there been any additional research?_

This is just one of the many things that fell out of feynman's brain when he
wasn't concentrating. AFAICT he produced ideas like this the same way the rest
of us produce farts.

~~~
acadien
It was his adviser's idea. Read the article.

~~~
unimpressive
Was the RTFA really necessary?

~~~
acadien
Good point, I shouldn't have been so rude.

------
Raphmedia
That's SCARY.

Imagine if someone or something were to destroy this electron?

Imagine, if we had split the electron instead and then BAM, no more space and
time.

~~~
mratzloff
Assuming its position distribution in time and space is the same in our future
as it is in our past, its destruction would have no impact on space and time,
because its past positions would continue to exist into our future.

------
has2k1
Nice little bit of New Age Physics.

------
a3voices
If this electron can travel faster than the speed of light, maybe other things
can too.

~~~
fennecfoxen
This isn't the case: the electron postulated can travel no faster than the
speed of light. It just happens to have a world-line which bounces back and
forth, a _lot_ , from the beginning of time to the end of time.

There's a variety of interesting theory-things which treat a particle's
absorption as an emission back in time, as well; the difference is that here
is the "same particle" tracing all those lines, instead of just one of those
lines.

------
avty
The Electric Universe Theory is also extremely intriguing.

