8 ms·

Testable theory suggests information has mass

60 points by Anon84 7y ago

pferde 7y ago
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 7y ago
  > 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...
  - pferde 7y ago
    Yes, you summarized what I feel is wrong with the experiment perhaps even better than me. They are trying to weigh not the information itself, but medium used to convey the information.
    - davedx 7y ago
      It that true, though? Does an electronic storage device with full storage have more electrons in it? I don't know enough about how modern memory works to say for sure.
      - pferde 7y ago
        That's not really the point. The point is, they would be measuring the weight of the electrons, in other words, the implementation-specific medium used to store the information. Not the information itself. I can see this discussion go very far into metaphysical. :)
        mathw 7y ago
        Well, what is information? Is it an abstract thing, or does it only exist in terms of the thing which is representing it? I don't have a clue, I just think it's a relevant question at this point.
      - blattimwind 7y ago
        Electrons are used as the information storage mechanism in flash memory, but the data is whitened (50 % one bits on average independent of the data input) before being stored. Hence, "the number of electrons" would not vary between an SSD storing only zeroes, and one only storing ones. But in any case, you would be measuring the mass of electrons and not the information they represent. This theory suggests that a storage device would have additional mass dependent on information content, so things like whitening / encryption would not matter. However, here is a question that immediately occurs: If I have a message with "informational mass" x, and encrypt it, does the encrypted message has the same informational mass, or is the mass of the encrypted message the same as a random message of the same length?
        consp 7y ago
        Since flash is based on a charge pump, doesn't it just move the electrons from the substrate or control gate to the floating gate? Or am I missing something here? In that case you do not have to account for the electron mass at all.
      - mpoloton 7y ago
        Electron rest mass is about 1E-31 Kg which is orders of magnitude more than the proposed estimated bit mass of 1E-38 Kg.
  - bognition 7y ago
    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.
    - ryandvm 7y ago
      Same as an SSD. Regardless of whether you saved anything on it the individual bits are either set or unset. It always has information on it, it just might not be _your_ information.
    - _carl_jung 7y ago
      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 7y ago
        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 7y ago
        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 7y ago
        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).
  - undecisive 7y ago
    Surely not though - we're talking about information. You don't need electricity flowing for the light switch to store information. In fact, the light switch could have no spring in it, allowing it to be in an infinity of different states. So let's imagine a board with two such light switches. I set one to 0.9998128376666.. and the other to 0.26757328888... - out of the infinite number of possibilities, how do we quantify the information that I've just stored in these light switches, to determine how much their weight should have changed? It's a silly question. It's a bit like saying "If a tree falls in the forest, do birds contain sodium?" Of course the two halves of the question are related tangentially, but putting them together like this is totally meaningless. Oooh... and nests are a thing, so, is it trees falling in the forest that causes nests? (dark matter)
- radarsat1 7y ago
  Weigh an SSD before and after storing data on it? That's so easy to do I have no idea why such an article would leave it as a theoretical. edit: since I have been downvoted, perhaps someone would like to clarify how my description differs from, "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."
  - pferde 7y ago
    The last paragraph of TFA explains why it is left theoretical. In short, lack of measuring accuracy.
  - Deukhoofd 7y ago
    > Unfortunately, taking the extremely small measurement needed to such precision may currently be unachievable. Vopson proposes the next step to getting answers could be developing a sensitive interferometer similar to LIGO or an ultra-sensitive Kibble balance. The article explains why it's not testable.
    - Brave-Steak 7y ago
      Or you could just store a crazy amount of information on one medium that's big enough. Can somebody calculate how much it would need to be before it's measurable with modern instruments?
      - Sean1708 7y ago
        From the paper: > For 1Tb device the estimated mass change is 2.5 × 10^-25 Kg. I don't actually know how precise we're currently able to measure mass, though.
        trentlott 7y ago
        A proton weighs ~10^-27 kg, so that's about 100 protons. I sincerely doubt we have masses that are quite that good - especially that which can take a high mass item (harddrive) and detect an atomic-scale change without being hideously noisy
- ravenstine 7y ago
  It seems like a modern version of the early 20th century experiment to weigh the human soul. https://en.wikipedia.org/wiki/21_grams_experiment https://en.wikipedia.org/wiki/21_grams_experiment
  - mrfusion 7y ago
    Well if the brain holds a huge amount of information this could actually explain those experiments. weird to think about.
    - dTal 7y ago
      Even funnier, the information lost when a human dies really is their soul! The real question is, how many bits is a human soul? (To be clear - this is definitely not the explanation for those experimental results. But it's fun to kid around!!)
- jerf 7y ago
  "He suggests taking mass measurements of a digital data storage device when it has full memory." I hope this is just fuzzification from the usual science journalism process, but I worry there may be some equivocation (in the logical sense) there. What the universe considers "information" and what we consider "information" do not have to be the same thing. They will certainly be related, and as human!information approaches universe!information density, they'd converge, but up here in the macroscopic world there's a lot of daylight between the two. Consider a simplified cell we use to store a bit, which can either have electrons piled up on one side for a 0, or equally piled up on an equal side for a 1. We humans might consider a drive full of random numbers to be full of information while a drive full of zeros is highly, highly compressible and thus nearly empty of information, but from the universe's point of view, we have exactly the same amount of excess "information" about which electrons are confined where no matter what we humanly store on this drive. That "information" would also constitute far more universe!bits than we could ever dream of storing human!bits on the same drive, while at the same time, not even remotely approaching the level we could hope to measure as mass. Human!information is a lower bound on universe!information, and not a particularly good one, either. It seems to me we have a decent grasp on what may constitute a "qubit" and how that may be information, but I've not seen a very solid discussion of what the universe may consider "information" in the arrangement of those qubits. I phrase it as "I've not seen" on purpose, since I'm not in the field. I do know I've seen very far-out speculation like the possibility gravity is somehow related to mass blocking the information flow in the universe in an asymmetric way resulting in a force, but IIRC that still had no discussion on what the information may be, beyond a mere aggregation of qubits. It's obviously there, but we don't know what it is. (Now there's a sentence that makes it sound like dark matter....) (Thinking about this simplified cell I gave above, my crazy thought would be, if "information" in the universe and "a configuration of mass-energy that maintains its state even though there's a field trying to push it out of the state" (such as the electrons staying in their trap even though they are electrostatically trying to push each other apart) were the same, then there would be a clean mechanism for "information" to "have mass", in the additional potential energies involved. A disorganized mass-energy system where everything is already at the lowest energy would have no information. But this is just crazy talk.)
- m463 7y ago
  Sort of reminds me of the question, "does a battery weigh the same when charged as when discharged?" (on the other hand, I remember lead-acid car batteries are more prone to freezing when discharged)
loourr 7y ago
What about a photon? If I use light to transmit information have I given it mass?
- nabla9 7y ago
  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 7y ago
    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 7y ago
      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.
vimman 7y ago
sounds about right?
davidmurdoch 7y ago
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 7y ago
The paper is open access: https://aip.scitation.org/doi/10.1063/1.5123794 https://aip.scitation.org/doi/10.1063/1.5123794
- jfengel 7y ago
  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 7y ago
    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-vopson(2065a4af-19b5-4624-8c75-e96822832377)/publications.html?pageSize=50&page=0 https://researchportal.port.ac.uk/portal/en/persons/melvin-v... [2]: https://www.port.ac.uk/about-us/structure-and-governance/our-people/our-staff/melvin-vopson https://www.port.ac.uk/about-us/structure-and-governance/our...
    - jfengel 7y ago
      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.
      - deleted 7y ago
        [deleted]
FabHK 7y ago
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-and-the-second-law/ https://www.scientificamerican.com/article/demons-engines-an... https://ecee.colorado.edu/~ecen4555/SourceMaterial/DemonsEnginesAndSecondLaw87.pdf https://ecee.colorado.edu/~ecen4555/SourceMaterial/DemonsEng...
- chrispeel 7y ago
  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.
FabHK 7y ago
Can empirically confirm. I keep learning, and gain about 1kg per year.
- lazyjones 7y ago
  I must be a bit older than you then, I'm gaining weight and forgetting things.
  - iezepov 7y ago
    So information has mass for sure, it's just that the sign is unclear.
- James_Henry 7y ago
  Then you're storing some 3.13*10^37 new bits per year. Congrats.
nabla9 7y ago
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 7y ago
  Newbie question, would this imply that there's something like an "information particle"?
  - krastanov 7y ago
    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).
    - 7y ago
Udik 7y ago
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.
mrfusion 7y ago
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)
mrfusion 7y ago
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 7y ago
  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 7y ago
    Hmm. But the heat could be dissipated.
    - krastanov 7y ago
      Oh, good point! But you can also just throw the hard drive out of the airlock ;)
    - ericlewis 7y ago
      true, but hard in a vacuum.
d--b 7y ago
> 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 7y ago
  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.
im3w1l 7y ago
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 7y ago
  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 7y ago
    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.
oefrha 7y ago
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.
skwirl 7y ago
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.
- mcrocop 7y ago
  Damn, that's deep. Brilliant.
- Sean1708 7y ago
  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-people/our-staff/melvin-vopson https://www.port.ac.uk/about-us/structure-and-governance/our...
- heavenlyblue 7y ago
  They are not random sequences of bits - they are very specific sequences of bits generated from a random stream.
karmakaze 7y ago
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).
undecisive 7y ago
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
mnowicki 7y ago
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?

60 points by Anon84 7y ago

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 7y ago
> 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...
- pferde 7y ago
  Yes, you summarized what I feel is wrong with the experiment perhaps even better than me. They are trying to weigh not the information itself, but medium used to convey the information.
  - davedx 7y ago
    It that true, though? Does an electronic storage device with full storage have more electrons in it? I don't know enough about how modern memory works to say for sure.
    - pferde 7y ago
      That's not really the point. The point is, they would be measuring the weight of the electrons, in other words, the implementation-specific medium used to store the information. Not the information itself. I can see this discussion go very far into metaphysical. :)
      - mathw 7y ago
        Well, what is information? Is it an abstract thing, or does it only exist in terms of the thing which is representing it? I don't have a clue, I just think it's a relevant question at this point.
    - blattimwind 7y ago
      Electrons are used as the information storage mechanism in flash memory, but the data is whitened (50 % one bits on average independent of the data input) before being stored. Hence, "the number of electrons" would not vary between an SSD storing only zeroes, and one only storing ones. But in any case, you would be measuring the mass of electrons and not the information they represent. This theory suggests that a storage device would have additional mass dependent on information content, so things like whitening / encryption would not matter. However, here is a question that immediately occurs: If I have a message with "informational mass" x, and encrypt it, does the encrypted message has the same informational mass, or is the mass of the encrypted message the same as a random message of the same length?
      - consp 7y ago
        Since flash is based on a charge pump, doesn't it just move the electrons from the substrate or control gate to the floating gate? Or am I missing something here? In that case you do not have to account for the electron mass at all.
    - mpoloton 7y ago
      Electron rest mass is about 1E-31 Kg which is orders of magnitude more than the proposed estimated bit mass of 1E-38 Kg.
- bognition 7y ago
  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.
  - ryandvm 7y ago
    Same as an SSD. Regardless of whether you saved anything on it the individual bits are either set or unset. It always has information on it, it just might not be _your_ information.
  - _carl_jung 7y ago
    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 7y ago
      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 7y ago
        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 7y ago
        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).
- undecisive 7y ago
  Surely not though - we're talking about information. You don't need electricity flowing for the light switch to store information. In fact, the light switch could have no spring in it, allowing it to be in an infinity of different states. So let's imagine a board with two such light switches. I set one to 0.9998128376666.. and the other to 0.26757328888... - out of the infinite number of possibilities, how do we quantify the information that I've just stored in these light switches, to determine how much their weight should have changed? It's a silly question. It's a bit like saying "If a tree falls in the forest, do birds contain sodium?" Of course the two halves of the question are related tangentially, but putting them together like this is totally meaningless. Oooh... and nests are a thing, so, is it trees falling in the forest that causes nests? (dark matter)
radarsat1 7y ago
Weigh an SSD before and after storing data on it? That's so easy to do I have no idea why such an article would leave it as a theoretical. edit: since I have been downvoted, perhaps someone would like to clarify how my description differs from, "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."
- pferde 7y ago
  The last paragraph of TFA explains why it is left theoretical. In short, lack of measuring accuracy.
- Deukhoofd 7y ago
  > Unfortunately, taking the extremely small measurement needed to such precision may currently be unachievable. Vopson proposes the next step to getting answers could be developing a sensitive interferometer similar to LIGO or an ultra-sensitive Kibble balance. The article explains why it's not testable.
  - Brave-Steak 7y ago
    Or you could just store a crazy amount of information on one medium that's big enough. Can somebody calculate how much it would need to be before it's measurable with modern instruments?
    - Sean1708 7y ago
      From the paper: > For 1Tb device the estimated mass change is 2.5 × 10^-25 Kg. I don't actually know how precise we're currently able to measure mass, though.
      - trentlott 7y ago
        A proton weighs ~10^-27 kg, so that's about 100 protons. I sincerely doubt we have masses that are quite that good - especially that which can take a high mass item (harddrive) and detect an atomic-scale change without being hideously noisy
ravenstine 7y ago
It seems like a modern version of the early 20th century experiment to weigh the human soul. https://en.wikipedia.org/wiki/21_grams_experiment https://en.wikipedia.org/wiki/21_grams_experiment
- mrfusion 7y ago
  Well if the brain holds a huge amount of information this could actually explain those experiments. weird to think about.
  - dTal 7y ago
    Even funnier, the information lost when a human dies really is their soul! The real question is, how many bits is a human soul? (To be clear - this is definitely not the explanation for those experimental results. But it's fun to kid around!!)
jerf 7y ago
"He suggests taking mass measurements of a digital data storage device when it has full memory." I hope this is just fuzzification from the usual science journalism process, but I worry there may be some equivocation (in the logical sense) there. What the universe considers "information" and what we consider "information" do not have to be the same thing. They will certainly be related, and as human!information approaches universe!information density, they'd converge, but up here in the macroscopic world there's a lot of daylight between the two. Consider a simplified cell we use to store a bit, which can either have electrons piled up on one side for a 0, or equally piled up on an equal side for a 1. We humans might consider a drive full of random numbers to be full of information while a drive full of zeros is highly, highly compressible and thus nearly empty of information, but from the universe's point of view, we have exactly the same amount of excess "information" about which electrons are confined where no matter what we humanly store on this drive. That "information" would also constitute far more universe!bits than we could ever dream of storing human!bits on the same drive, while at the same time, not even remotely approaching the level we could hope to measure as mass. Human!information is a lower bound on universe!information, and not a particularly good one, either. It seems to me we have a decent grasp on what may constitute a "qubit" and how that may be information, but I've not seen a very solid discussion of what the universe may consider "information" in the arrangement of those qubits. I phrase it as "I've not seen" on purpose, since I'm not in the field. I do know I've seen very far-out speculation like the possibility gravity is somehow related to mass blocking the information flow in the universe in an asymmetric way resulting in a force, but IIRC that still had no discussion on what the information may be, beyond a mere aggregation of qubits. It's obviously there, but we don't know what it is. (Now there's a sentence that makes it sound like dark matter....) (Thinking about this simplified cell I gave above, my crazy thought would be, if "information" in the universe and "a configuration of mass-energy that maintains its state even though there's a field trying to push it out of the state" (such as the electrons staying in their trap even though they are electrostatically trying to push each other apart) were the same, then there would be a clean mechanism for "information" to "have mass", in the additional potential energies involved. A disorganized mass-energy system where everything is already at the lowest energy would have no information. But this is just crazy talk.)
m463 7y ago
Sort of reminds me of the question, "does a battery weigh the same when charged as when discharged?" (on the other hand, I remember lead-acid car batteries are more prone to freezing when discharged)

loourr 7y ago

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

nabla9 7y ago
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 7y ago
  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 7y ago
    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.

vimman 7y ago

sounds about right?

davidmurdoch 7y ago

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 7y ago

The paper is open access: https://aip.scitation.org/doi/10.1063/1.5123794 https://aip.scitation.org/doi/10.1063/1.5123794

jfengel 7y ago
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 7y ago
  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-vopson(2065a4af-19b5-4624-8c75-e96822832377)/publications.html?pageSize=50&page=0 https://researchportal.port.ac.uk/portal/en/persons/melvin-v... [2]: https://www.port.ac.uk/about-us/structure-and-governance/our-people/our-staff/melvin-vopson https://www.port.ac.uk/about-us/structure-and-governance/our...
  - jfengel 7y ago
    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.
    - deleted 7y ago
      [deleted]

FabHK 7y ago

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-and-the-second-law/ https://www.scientificamerican.com/article/demons-engines-an... https://ecee.colorado.edu/~ecen4555/SourceMaterial/DemonsEnginesAndSecondLaw87.pdf https://ecee.colorado.edu/~ecen4555/SourceMaterial/DemonsEng...

chrispeel 7y ago
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.

FabHK 7y ago

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

lazyjones 7y ago
I must be a bit older than you then, I'm gaining weight and forgetting things.
- iezepov 7y ago
  So information has mass for sure, it's just that the sign is unclear.
James_Henry 7y ago
Then you're storing some 3.13*10^37 new bits per year. Congrats.

nabla9 7y ago

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 7y ago
Newbie question, would this imply that there's something like an "information particle"?
- krastanov 7y ago
  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).
  - 7y ago

Udik 7y ago

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.

mrfusion 7y ago

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)

mrfusion 7y ago

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 7y ago
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 7y ago
  Hmm. But the heat could be dissipated.
  - krastanov 7y ago
    Oh, good point! But you can also just throw the hard drive out of the airlock ;)
  - ericlewis 7y ago
    true, but hard in a vacuum.

d--b 7y ago

> 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 7y ago
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.

im3w1l 7y ago

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 7y ago
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 7y ago
  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.

oefrha 7y ago

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.

skwirl 7y ago

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.

mcrocop 7y ago
Damn, that's deep. Brilliant.
Sean1708 7y ago
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-people/our-staff/melvin-vopson https://www.port.ac.uk/about-us/structure-and-governance/our...
heavenlyblue 7y ago
They are not random sequences of bits - they are very specific sequences of bits generated from a random stream.

karmakaze 7y ago

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).

undecisive 7y ago

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

mnowicki 7y ago

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?