
Testable theory suggests information has mass - Anon84
https://aip.scitation.org/doi/10.1063/1.5126530
======
nabla9
The assumption seems to be that you can transfer mass and energy into
information in a way that subtracts from total mass+energy of the system but
still shows up when weighed.

To test the hypothesis it's not enough just to weigh the memory. You must
ensure that the energy stored in the memory has not been increased, because
energy increases the weight of the memory device. (relaxed spring weighs less
than tensed spring, storing energy in capacitors increases the weight of the
memory).

The paper:
[https://aip.scitation.org/doi/10.1063/1.5123794](https://aip.scitation.org/doi/10.1063/1.5123794)

>Here we formulate a new principle of mass-energy-information equivalence
proposing that a bit of information is not just physical, as already
demonstrated, but it has a finite and quantifiable mass while it stores
information.

(...)

>Assuming that all the missing dark matter is in fact information mass, the
initial estimates (to be reported in a different article) indicate that ∼10^93
bits would be sufficient to explain all the missing dark matter in the visible
Universe. Remarkably, this number is reasonably close to another estimate of
the Universe information bit content of ∼10^87 given by Gough in 2008 via a
different approach.12 In fact, one could argue that information is a distinct
form of matter, or the 5th state, along the other four observable solid,
liquid, gas, and plasma states of matter. It is expected that this work will
stimulate further theoretical and experimental research, bringing the
scientific community one-step closer to understanding the abstract nature of
matter, energy and information in the Universe.

ps. AIP advances is so called scientific mega journal. It has very low
selectivity and don't select articles based on importance. They are "peer
reviewed" only in the lowest criteria possible.

~~~
choxi
Newbie question, would this imply that there's something like an "information
particle"?

~~~
krastanov
Not in any of the usual meanings of "particle" (an "excitation of a quantum
field", which of course is not a particularly elucidating explanation if you
are lacking context).

~~~
mojomark
In Light Emitting Diodes, electrons move across the electron transport layer,
while "hole" particles move through the hole transport, where they meet at the
heterojunction to combine and emit photon particles. Holes aren't really like
other atomic particles, rather they represent the lack of an electron in an
energy field that has an affinity for electrons. But it's still a type of
manifestation of energy (or lack thereof), thus represents a unit of mass
(albeit negative), which effectively signifies the presence of a manipulatable
minute piece of negative matter - the definition of a particle.

So, I don't see why you couldn't use the particle label when referring to
information. How about an "infon"?

~~~
krastanov
Yes, holes exist and are a useful formalism. But you are wrong, holes very
much behave like other elementary particles (pseudo-particles), and you get to
call these things particles, exactly because they behave like excitations of a
field.

If you insist, sure, you can make up an infon and call it a particle. However,
it would not behave like anything a physicist would call a particle, nor would
it use any of the mathematical tools that were developed to deal with
particles, nor it would provide any useful intuition or insight, nor would it
provide any pedagogical value. And at that point why bother calling it a
particle if it does not behave like one.

------
pferde
From TFA: "“This idea is laboratory testable in principle,” said Vopson. He
suggests taking mass measurements of a digital data storage device when it has
full memory. If it has more mass than when the device’s memory is cleared,
then that would show the mass-energy-information equivalence is correct."

While the idea is interesting, the actual proposed experiment is laughable.
It's like suggesting that a mechanical light switch should have different
weight when switched on or off.

~~~
Anon84
> a mechanical light switch should have different weight when switched on or
> off.

Well, in principle it should have a different weight to account for the extra
electrons moving around when it’s turned on. Every time you have a change in
charge you have a corresponding mas change.

My problem with this idea is the fact that not all information is electronic
in nature, in which case you would be arguing that the weight of a completed
puzzle is different than the total weight of the individual pieces, for
example.

In general, this would imply that changes in entropy would correspond to
changes in mass...

~~~
bognition
It's more complicated than that. A single light switch stores exactly 1 bit of
information. Its either on or off and both positions convey the exact same
amount of information.

~~~
_carl_jung
This raises what I view to be a falsification by counter-example of the
original premise. If information (and not _the representation of_ information)
has mass, then does a piece of uncompressed information weight the same amount
as the compressed information?

Furthermore, information is related to interpretation. A string of bits may be
an uncompressed text file, a set of numbers, a compressed image, etc. But it's
always the same amount of bits. How can my interpretation of that set of bits
affect its mass?

~~~
krastanov
There are measures that do not depend on interpretation. Entropy of the
content for instance. This is what people usually refer to in this context and
the ideas of the article have actually been known to physicists for decades.

~~~
_carl_jung
I'm out of my depth here as I've never studied information theory. I suppose
there's a larger gap between the theory and the practical aspect of the title
of this article than I first imagined!

~~~
krastanov
Yeah, our everyday technology is maaaany orders of magnitude away from where
this would be detectable. However, it is still important topic if we want to
design extreme efficiency computing hardware (and already studied among
researchers that want to make nanotech).

------
skwirl
Let's say I have three 1TB drives - A, B, and C. A contains 1TB of meaningful
data. B contains a sequence of randomly generated bits to be used as a one-
time pad for encryption. I use B to encrypt the data on A, store this data
onto C, and then destroy A.

B and C now can be combined to retrieve the information that was once stored
on A. But B and C by themselves are just random sequences of bits. Where is
the information, and therefore mass, of A, which still exists in B and C? If
it is in one or both of B and C then I can destroy the information (and
therefore reduce mass) in one by destroying the other.

~~~
Sean1708
Remember the paper is talking about entropy[1] rather than any kind of human-
encoded information.

[1]: [https://www.port.ac.uk/about-us/structure-and-
governance/our...](https://www.port.ac.uk/about-us/structure-and-
governance/our-people/our-staff/melvin-vopson)

------
FabHK
One of the most interesting articles I ever read was in SciAm, arguing (from a
thought experiment, Maxwell's Demon [1]) that information needs some minimum
energy to be erased [2] (=reset to a low entropy state). Thus, there's
definitely a connection between energy and information. Given the known
connection between energy and mass, this would establish the final leg of the
triangle.

[1]
[https://en.wikipedia.org/wiki/Maxwell's_demon](https://en.wikipedia.org/wiki/Maxwell's_demon)

[2] Charles H. Bennett _Demons, Engines and the Second Law_ from 1987.

[https://www.scientificamerican.com/article/demons-engines-
an...](https://www.scientificamerican.com/article/demons-engines-and-the-
second-law/)

[https://ecee.colorado.edu/~ecen4555/SourceMaterial/DemonsEng...](https://ecee.colorado.edu/~ecen4555/SourceMaterial/DemonsEnginesAndSecondLaw87.pdf)

~~~
chrispeel
I'm not certain that Maxwell's demon establishes enough of a connection
between energy and information. I think you want more than just a connection,
rather some kind of equivalence.

------
d--b
> He suggests taking mass measurements of a digital data storage device when
> it has full memory. If it has more mass than when the device’s memory is
> cleared, then that would show the mass-energy-information equivalence is
> correct.

Er... What?

What does it mean to "delete" information here? You put some movies on a usb
drive, and then set everything to 0? and see if there's a mass difference? But
a string of 0s is still information, no?

~~~
krastanov
Yeah, as I mentioned in a sibling comment, erasure of data is an irreversible
process that (because of thermodynamics) will always create heat (even of
everything is a efficient as the laws of the universe permit). That heat is
energy and it has mass. It is actually straightforward to prove it would have
the same mass as the initial information pattern.

A string of zeroes and a random string do have different amount of entropy, so
transforming between them requires energy.

------
davidmurdoch
Reminds me of Micheal Stevens's (from Vsauce) TEDx talk titled "How Much Does
a Video Weigh?". [https://youtu.be/yzQDFKY2uEI](https://youtu.be/yzQDFKY2uEI)

------
mxcrossb
The paper is open access:
[https://aip.scitation.org/doi/10.1063/1.5123794](https://aip.scitation.org/doi/10.1063/1.5123794)

~~~
jfengel
I'm perplexed at what "AIP Advances" is supposed to be. This paper isn't an
advance of any sort. It's an application of some decades-old formulas you can
grab off Wikipedia; a high schooler could apply them to get this result. It
adds nothing to "testability" (and is in fact wrong in its understanding of
what "information" in a hard drive really is).

The journal has an impact factor of 1.5. For comparison, Science and Nature
are in the 40s. This was a cute letter, but it should not have passed peer-
review, whether it's open-access or not, because it contributes nothing novel.

~~~
Sean1708
Weirdly it's not like the author is some crackpot nobody, he has actual papers
under his belt[1] and is a Senior Lecturer[2] (although not at a particularly
prestigious university, admittedly).

[1]:
[https://researchportal.port.ac.uk/portal/en/persons/melvin-v...](https://researchportal.port.ac.uk/portal/en/persons/melvin-
vopson\(2065a4af-19b5-4624-8c75-e96822832377\)/publications.html?pageSize=50&page=0)

[2]: [https://www.port.ac.uk/about-us/structure-and-
governance/our...](https://www.port.ac.uk/about-us/structure-and-
governance/our-people/our-staff/melvin-vopson)

~~~
jfengel
His other papers are all in solid-state physics. He's a real scientist playing
around outside his domain, discovering a well-known result, and writing a fun
letter about it to a low-impact journal.

All of which is fine. It just requires a bit more context than the headline
yields. If this had linked to his blog, it would make a lot more sense.

------
mrfusion
Hey just a thought experiment. Future spacecraft flying through space at say
.9c. Mid flight it erases its enormous hard drive and losses a few grams.

Does it speed up? How is momentum conserved?

~~~
krastanov
No, because the erasure of the information (irreversible process) will create
heat (this is one of the postulates of thermodynamics). Heat is energy which
also has mass. It is fascinating how nature provides for these amazing "near
coincidences" and then finds a way to close the loophole.

~~~
mrfusion
Hmm. But the heat could be dissipated.

~~~
krastanov
Oh, good point! But you can also just throw the hard drive out of the airlock
;)

------
undecisive
I just had to check my computer's calendar - nope, not April 1st yet.

This is absolutely idiotically bonkers.

Information can be stored with mass, but is not the same as mass. They are not
equal. I can't believe anybody is even trying to think up ways to disprove
something so momentously bonkers. I mean sure, that's what science does... but
buhhhhh

------
oefrha
Read the paper. Unfortunately this “radical idea” operates completely within
known thermodynamics and is just calling energy associated with thermodynamic
non-equilibrium “mass of information”. Energy _is_ information in that sense,
so this adds nothing.

------
karmakaze
This article fails at being precise about what 'nformation' is. Some physical
pattern only represents a '0' or '1' if we mean it to.

> Experiments have proven the process of deleting a bit of information
> dissipates heat energy, but after information is created, it can be stored
> with no energy loss.

To be precise here 'deleting' is a reduction in the number of possible states
of a closed system. All '0's or all '1's is not a state of low information.
They are both highly ordered states. The state of no information is total
randomness, as in heat death. It does require energy to maintain (i.e. keep
storing) for information (an ordered state).

------
mnowicki
Are they implying that a storage drive with bits organized to store specific
data(say an mp4 file, or the meaning of life) will way more than a drive with
randomly arranged bits? If not then aren't they just measuring whatever
mechanism is used to physically represent the bits, and not the information
itself?

And if so that does seem quite unbelievable. Wouldn't that mean that if you
had 2 tiny harddrives that both stored the number 3.14, one harddrive happened
to store that number after randomly assigning the bits and one harddrive
purposely had 3 digits of PI saved on, the one that was purposely storing the
number would weigh more?

------
Udik
For what I understand, the proposal- with its suggestion that it may account
for dark matter- seems to imply that two different arrangements of exactly the
same particles can have different mass, depending on how much information
those arrangements encode. Because otherwise, if "information" is intrinsic to
each particle and not a collective property, then I don't see how its mass
wouldn't be already accounted for by the particles' mass.

------
im3w1l
Due to the particularities of how a storage device works, a 1 should be a tiny
amount heavier (or lighter, Idk which way it goes) than a 0.

~~~
Sean1708
What kind of storage device? I'm fairly sure in a HDD the 1 and 0 states have
the same energy, and from what I know about SSDs I think the same is true
there.

~~~
im3w1l
I don't have a great understanding of SSD's but I believe the data is stored
as charge in floating gates. And this charge should have weight.

For HDD's I think I was wrong but there is on the other hand an interaction
effect between nearby bits. If nearby magnetic domains try to repel each other
it has higher energy.

------
mrfusion
Wow this is such a cool idea. Here are some far out sci fi ideas this might
lead to:

Create and destroy mass at will on a spacecraft to make some kind of warp
drive.

Artificial gravity on a spacecraft.

Create a black hole with information that you can turn on and off.

(obviously not possible with today’s technology. You’d need unbelievably dense
information storage mediums)

------
loourr
What about a photon? If I use light to transmit information have I given it
mass?

~~~
nabla9
You forgot the mass-energy equivalence. Photon has no rest mass, but it's
energy is equivalent to some mass.

Photon's stress–energy tensor causes similar effect on gravitational field as
tiny amount of mass equivalent to the energy of a photon.

~~~
superfist
So basically we have rest mass and relativistic mass. How those two compare?
And when we say: energy - mass equivalence we actually mean energy -
relativistic mass equivalence?

~~~
YayamiOmate
No. You gotta be extra careful when you introduce relativistic mass.

Photon has momentum, zero rest mass. Energy mass equivalence says that you can
annihilate mass to create a massless particle. This is true for all the
observers.

Relativistic mass is a perceived mass dependent on the observer.

------
FabHK
Can empirically confirm. I keep learning, and gain about 1kg per year.

~~~
lazyjones
I must be a bit older than you then, I'm gaining weight and forgetting things.

~~~
iezepov
So information has mass for sure, it's just that the sign is unclear.

------
vimman
sounds about right?

