6 ms·

Information Has Mass

54 points by 00117 5y ago

MPSimmons 5y ago
The headline is misleading. This paper proposes an experiment to determine if the theory that information has mass is true.
drfuchs 5y ago
On the contrary. Take a punch-card, stick it in your 029 keypunch, and add 80 bytes of information to it by typing away. Now it weighs less than when you started. Information has negative mass.
- bsedlm 5y ago
  counter example. consider that instead of punching out the holes, you added an ink blot, the ink is somehow reflective and thus is read by the machine (or whatever). as the ink has a weight it now weighs more than when you started. Information has regular mass. hence some prior assumption is mistaken and we could now prove something by contradiction. now then, somebody please tell me if a proof by contradiction holds in constructive logic.
  - drdeca 5y ago
    Showing that X implies a contradiction is showing not X in intuitionistic/constructive logic, yes. However, you can’t show X by assuming not X and reaching a contradiction. By doing so you would only show not(not(X))
  - rolandog 5y ago
    Agreed; furthermore, your example is analogous to the classical way to answer a test by filling in the answer-sheet's circles with graphite pencils.
- denton-scratch 5y ago
  It has been said that a punched-card is the least-efficient form of data storage ever invented. The data is stored in the form of holes in the card. The card's only purpose therefore is to hold the holes in place, so it is 100% redundant.
  - throwaheyy 5y ago
    Interesting perspective. Without the card around them though, the holes don’t exist.
- lodovic 5y ago
  But all the paper chips that you punched away are information too. So it's zero sum.
- amelius 5y ago
  In a deterministic universe your typing doesn't add any information; any information was already there from the start.
- jrootabega 5y ago
  The entire universe is holestuff and is already there by default. You add in the paper to tell the reader where the holes AREN'T.
ajkjk 5y ago
This paper feels very unconvincing. It seems to just assume that there is some intrinsic entropy inside a particle which, by virtue of their annihilation, must be released. I'm fairly sure that is not at all what the Landauer limit is talking about. This cited paper https://aip.scitation.org/doi/10.1063/5.0064475 https://aip.scitation.org/doi/10.1063/5.0064475 comes up a with a number and says it's intrinsic in each particle, but.. that just seems so sketchy. The Landauer limit says: since entropy can't be destroyed, if an irreversible computation takes place -- if a bit is 'erased' -- the entropy must be released a heat. Then, using dE = T dS, that change in entropy ought to correspond to a change in energy. Nowhere in this is it claimed that particles store intrinsic bits of information. It's just talking about data that is modeled in the _state_ of a system. Erasing a bit means collapsing two states of the system into one. Also, maybe I'm being unfair here, but I'd guess that no paper about entropy that starts with "digital information storage technologies have radically transformed our modern society" is going to end up being good.
- mpalmer 5y ago
  "Modelled" is exactly it. It's a mapping of meaning to changes in various states. Not an expert and I know counterintuitive phenomena exist, but at bottom it makes way more sense that information is the effect of energy, not the cause of mass. It's a property of energy transfer that incidentally requires you to take into account the existence of some entity to interpret/record/act on it. So how can such a thing as information have mass? Something must be backwards here. What is information without its receiving entities, be they computers, signal relays, microphones or people? Or hard drives? Just changes in energy that sometimes change mass as well. Any change in mass you care to measure is bound to change the information inherent in the object. That's the direction of the relationship: The change in mass/energy leads to the information, not the other way around. For that matter, am I really making a sheet of paper heavier when I run it through a Braille printer? The example of the hard drive doesn't really provide clarity on this.
  - derbOac 5y ago
    Yeah I suddenly had very similar questions and then read your comment. If a bit exists but there's no one to encode it, does it inform? Seems like a lot of what we think of as information is really "potential information" along the lines of potential energy. Also surprising lack of quantum physics in the article. I'd be interested in what someone in the field of quantum physics or computation would have to say about these issues. I do research in information theory but in a totally different way.
fgh 5y ago
I don't see a convincing reason why information conservation would need two additional photons. The author mentions himself in the conclusions that the standard two photons of the annihilation process could carry the additional energy.
yayr 5y ago
Can someone explain to me, what actually constitutes that a particle has information or has no information? I.e., what would actually cause a change of this state? I would expect, that having just 0 or 1 alone would not. Maybe it is related to an observer/environment, i.e. the reduction of the wave superposition to certain possible states...
thro1 5y ago
Just a warning: professor A Dońda in the book “The Memoirs of a Space Traveler: Further Reminiscences of Ijon Tichy” (1973, by Stanislaw Lem) made already an experiment in such matter: while transforming information into mass he reached critical mass - what resulted in the disappearance of the contents of all computer data banks and collapse of human civilization.

54 points by 00117 5y ago

The headline is misleading. This paper proposes an experiment to determine if the theory that information has mass is true.

drfuchs 5y ago

On the contrary. Take a punch-card, stick it in your 029 keypunch, and add 80 bytes of information to it by typing away. Now it weighs less than when you started. Information has negative mass.

bsedlm 5y ago
counter example. consider that instead of punching out the holes, you added an ink blot, the ink is somehow reflective and thus is read by the machine (or whatever). as the ink has a weight it now weighs more than when you started. Information has regular mass. hence some prior assumption is mistaken and we could now prove something by contradiction. now then, somebody please tell me if a proof by contradiction holds in constructive logic.
- drdeca 5y ago
  Showing that X implies a contradiction is showing not X in intuitionistic/constructive logic, yes. However, you can’t show X by assuming not X and reaching a contradiction. By doing so you would only show not(not(X))
- rolandog 5y ago
  Agreed; furthermore, your example is analogous to the classical way to answer a test by filling in the answer-sheet's circles with graphite pencils.
denton-scratch 5y ago
It has been said that a punched-card is the least-efficient form of data storage ever invented. The data is stored in the form of holes in the card. The card's only purpose therefore is to hold the holes in place, so it is 100% redundant.
- throwaheyy 5y ago
  Interesting perspective. Without the card around them though, the holes don’t exist.
lodovic 5y ago
But all the paper chips that you punched away are information too. So it's zero sum.
amelius 5y ago
In a deterministic universe your typing doesn't add any information; any information was already there from the start.
jrootabega 5y ago
The entire universe is holestuff and is already there by default. You add in the paper to tell the reader where the holes AREN'T.

ajkjk 5y ago

This paper feels very unconvincing. It seems to just assume that there is some intrinsic entropy inside a particle which, by virtue of their annihilation, must be released. I'm fairly sure that is not at all what the Landauer limit is talking about. This cited paper https://aip.scitation.org/doi/10.1063/5.0064475 https://aip.scitation.org/doi/10.1063/5.0064475 comes up a with a number and says it's intrinsic in each particle, but.. that just seems so sketchy. The Landauer limit says: since entropy can't be destroyed, if an irreversible computation takes place -- if a bit is 'erased' -- the entropy must be released a heat. Then, using dE = T dS, that change in entropy ought to correspond to a change in energy. Nowhere in this is it claimed that particles store intrinsic bits of information. It's just talking about data that is modeled in the _state_ of a system. Erasing a bit means collapsing two states of the system into one. Also, maybe I'm being unfair here, but I'd guess that no paper about entropy that starts with "digital information storage technologies have radically transformed our modern society" is going to end up being good.

mpalmer 5y ago
"Modelled" is exactly it. It's a mapping of meaning to changes in various states. Not an expert and I know counterintuitive phenomena exist, but at bottom it makes way more sense that information is the effect of energy, not the cause of mass. It's a property of energy transfer that incidentally requires you to take into account the existence of some entity to interpret/record/act on it. So how can such a thing as information have mass? Something must be backwards here. What is information without its receiving entities, be they computers, signal relays, microphones or people? Or hard drives? Just changes in energy that sometimes change mass as well. Any change in mass you care to measure is bound to change the information inherent in the object. That's the direction of the relationship: The change in mass/energy leads to the information, not the other way around. For that matter, am I really making a sheet of paper heavier when I run it through a Braille printer? The example of the hard drive doesn't really provide clarity on this.
- derbOac 5y ago
  Yeah I suddenly had very similar questions and then read your comment. If a bit exists but there's no one to encode it, does it inform? Seems like a lot of what we think of as information is really "potential information" along the lines of potential energy. Also surprising lack of quantum physics in the article. I'd be interested in what someone in the field of quantum physics or computation would have to say about these issues. I do research in information theory but in a totally different way.

fgh 5y ago

I don't see a convincing reason why information conservation would need two additional photons. The author mentions himself in the conclusions that the standard two photons of the annihilation process could carry the additional energy.

yayr 5y ago

Can someone explain to me, what actually constitutes that a particle has information or has no information? I.e., what would actually cause a change of this state? I would expect, that having just 0 or 1 alone would not. Maybe it is related to an observer/environment, i.e. the reduction of the wave superposition to certain possible states...

thro1 5y ago

Just a warning: professor A Dońda in the book “The Memoirs of a Space Traveler: Further Reminiscences of Ijon Tichy” (1973, by Stanislaw Lem) made already an experiment in such matter: while transforming information into mass he reached critical mass - what resulted in the disappearance of the contents of all computer data banks and collapse of human civilization.