3 ms·

This is utter nonsense. Let’s play along: Take a 2 TiB flash drive. That’s 1e13 bytes or 1e16 bits. Suppose it’s one electron per bit. That’s approaching 1% o

by amluto 4y ago

This is utter nonsense. Let’s play along: Take a 2 TiB flash drive. That’s 1e13 bytes or 1e16 bits. Suppose it’s one electron per bit. That’s approaching 1% of a Coulomb! So you take two flash drives, charge them up, and hold them 1cm apart, and they fly apart with several hundred meganewtons of force! The electrostatic force is strong! This is, of course, completely wrong. When you write to flash, you are moving electrons around, not adding net electrons. The whole device stays electrically neutral (on average), and any mass change is due solely to minuscule relativistic effects if you add or remove energy.

Misdicorl 4y ago
They made a coulomb bomb https://gravityandlevity.wordpress.com/2013/05/22/what-if-i-were-1-charged/ https://gravityandlevity.wordpress.com/2013/05/22/what-if-i-... > I worked on all sorts of problems that involved the Coulomb interaction, and occasionally my proposed solution would be very wrong. The worst kind of wrong was the one that made my advisor remark “What you just created is a Coulomb bomb,” which meant that I had proposed something that wasn’t neutral on the large scale.
NotYourLawyer 4y ago
Right. The only actual effect would be like, having two charged (or two uncharged? maybe?) elements right next to each other entails some repulsive force, and so it takes additional energy to get to that state. That energy has mass via E=mc^2.
nayuki 4y ago
Exactly, I was going to point out the same thing. The flash cells might be charged or discharged of electrons, but the whole flash drive can't have a net charge or else you will certainly feel it. And because no solid/liquid/gaseous matter is exchanged between the computer and flash drive, there are no positive particles (nuclei/protons) moving either. This is similar to what it means to "charge" a capacitor. It doesn't mean injecting or removing electrons from it, because that would cause a net charge. It actually means shifting electrons from one electrode to the other, separated by an insulated gap. http://amasci.com/emotor/cap1.html http://amasci.com/emotor/cap1.html
- im3w1l 4y ago
  Calling it a shift is not right either. It's not the same electron that leaves one side and makes it way to the other. Electrons injected on one side and removed on the other.
  - nayuki 4y ago
    True. It's not the same electron... but electrons are also perfectly fungible. Quantum physics guarantees that.
FooBarBizBazz 4y ago
Here we see the effects of a computer science education on the author. Not enough physics.
- Aperocky 4y ago
  Don't blame this on CS, this is just Dunning-Kruger effect in action.
  - hgsgm 4y ago
    DK doesn't exist anywhere near what is commonly claimed. Ironically, that makes a Dunning-Kruger Effect effect. https://gwern.net/doc/iq/2020-gignac.pdf https://gwern.net/doc/iq/2020-gignac.pdf Do you think a physicist would be less certain that OP is wrong, than how certain OP is that he is right?
    - Aperocky 4y ago
      > Do you think a physicist would be less certain that OP is wrong, than how certain OP is that he is right? This is not the correct application of the effect. A physicist would have been sure about this particular case being wrong, but would likely be a lot more careful and concise about what he's talking about. Also a physicist is supposed to be more confident, as they are on the far right side of the curve. Being at the bottom of that curve is reserved for folks like me who rely on common sense but cannot be certain outside of extremely basic cases like knowing that electrons are not leaving the USB en masse.
Sharlin 4y ago
Never mind the difficulty of stuffing so many electrons in a space the size of a flash drive, and keeping them contained… (Also, 2 TiB is just 2e12 bytes, and 2e12 bytes only equals 1.6e13 bits, it’s log2(8) that’s 3, but that doesn’t really affect your conclusion.)
- jwilk 4y ago
  $ units -t 'coulombconst * (2 TiB * atomiccharge/bit / cm) ** 2' 714.00592 kg m / s^2 Not quite meganewtons, but still a lot.
- amluto 4y ago
  Sigh, I mixed up some powers of two with powers of ten in my head.
  - Sharlin 4y ago
    Yeah, I figured =D
55873445216111 4y ago
Also consider that most high density Flash today is made from TLC cells which have 8 distinct Vt levels each. That means in average case (i.e. random data) there is a minimum of 3.5 electrons per cell required. In reality, much more than 1 electron is required to store a 0 or 1 with any level of reliability. On the order of 10s to 100s of electrons per bit even on leading processes.
upofadown 4y ago
Since this is all silly anyways... What about the mechanical strain caused by the charges? Would the device be more compressed due to the attraction between the opposite charges associated with charged bits? Since the device is in air, it would then displace less air. Even though the device mass would be the same, the weight would be more.
hgsgm 4y ago
How does one send this message to BBC? They should be ashamed of themselves.

by amluto 4y ago

Misdicorl 4y ago

They made a coulomb bomb https://gravityandlevity.wordpress.com/2013/05/22/what-if-i-were-1-charged/ https://gravityandlevity.wordpress.com/2013/05/22/what-if-i-... > I worked on all sorts of problems that involved the Coulomb interaction, and occasionally my proposed solution would be very wrong. The worst kind of wrong was the one that made my advisor remark “What you just created is a Coulomb bomb,” which meant that I had proposed something that wasn’t neutral on the large scale.

NotYourLawyer 4y ago

Right. The only actual effect would be like, having two charged (or two uncharged? maybe?) elements right next to each other entails some repulsive force, and so it takes additional energy to get to that state. That energy has mass via E=mc^2.

nayuki 4y ago

Exactly, I was going to point out the same thing. The flash cells might be charged or discharged of electrons, but the whole flash drive can't have a net charge or else you will certainly feel it. And because no solid/liquid/gaseous matter is exchanged between the computer and flash drive, there are no positive particles (nuclei/protons) moving either. This is similar to what it means to "charge" a capacitor. It doesn't mean injecting or removing electrons from it, because that would cause a net charge. It actually means shifting electrons from one electrode to the other, separated by an insulated gap. http://amasci.com/emotor/cap1.html http://amasci.com/emotor/cap1.html

im3w1l 4y ago
Calling it a shift is not right either. It's not the same electron that leaves one side and makes it way to the other. Electrons injected on one side and removed on the other.
- nayuki 4y ago
  True. It's not the same electron... but electrons are also perfectly fungible. Quantum physics guarantees that.

FooBarBizBazz 4y ago

Here we see the effects of a computer science education on the author. Not enough physics.

Aperocky 4y ago
Don't blame this on CS, this is just Dunning-Kruger effect in action.
- hgsgm 4y ago
  DK doesn't exist anywhere near what is commonly claimed. Ironically, that makes a Dunning-Kruger Effect effect. https://gwern.net/doc/iq/2020-gignac.pdf https://gwern.net/doc/iq/2020-gignac.pdf Do you think a physicist would be less certain that OP is wrong, than how certain OP is that he is right?
  - Aperocky 4y ago
    > Do you think a physicist would be less certain that OP is wrong, than how certain OP is that he is right? This is not the correct application of the effect. A physicist would have been sure about this particular case being wrong, but would likely be a lot more careful and concise about what he's talking about. Also a physicist is supposed to be more confident, as they are on the far right side of the curve. Being at the bottom of that curve is reserved for folks like me who rely on common sense but cannot be certain outside of extremely basic cases like knowing that electrons are not leaving the USB en masse.

Sharlin 4y ago

Never mind the difficulty of stuffing so many electrons in a space the size of a flash drive, and keeping them contained… (Also, 2 TiB is just 2e12 bytes, and 2e12 bytes only equals 1.6e13 bits, it’s log2(8) that’s 3, but that doesn’t really affect your conclusion.)

jwilk 4y ago
$ units -t 'coulombconst * (2 TiB * atomiccharge/bit / cm) ** 2' 714.00592 kg m / s^2 Not quite meganewtons, but still a lot.
amluto 4y ago
Sigh, I mixed up some powers of two with powers of ten in my head.
- Sharlin 4y ago
  Yeah, I figured =D

55873445216111 4y ago

Also consider that most high density Flash today is made from TLC cells which have 8 distinct Vt levels each. That means in average case (i.e. random data) there is a minimum of 3.5 electrons per cell required. In reality, much more than 1 electron is required to store a 0 or 1 with any level of reliability. On the order of 10s to 100s of electrons per bit even on leading processes.

upofadown 4y ago

Since this is all silly anyways... What about the mechanical strain caused by the charges? Would the device be more compressed due to the attraction between the opposite charges associated with charged bits? Since the device is in air, it would then displace less air. Even though the device mass would be the same, the weight would be more.

hgsgm 4y ago

How does one send this message to BBC? They should be ashamed of themselves.