5 ms·
It makes me wonder, is there a hard physical limit on what is possible for data storage density? Hardrives are roughly 1Tb/in^2 in areal density right now. SSD
by crispyambulance 8y ago
It makes me wonder, is there a hard physical limit on what is possible for data storage density?
Hardrives are roughly 1Tb/in^2 in areal density right now. SSD's are a little better.
This one using hydrogen atoms is ~100x better.
Hydrogen atoms are pretty damn small. Aside from improvements with 2D packing factor, is this pretty much the limit?
- sacheendra 8y agohttps://en.m.wikipedia.org/wiki/Bekenstein_bound https://en.m.wikipedia.org/wiki/Bekenstein_bound It gives the maximum amount of data in space before collapsing into a black hole.
- akvadrako 8y agoAnd it's something like 10^35 hellabits / mm³, so we have a ways to go.
- mrguyorama 8y agoMaximum mathematical is not the same as maximum achievable
- crispyambulance 8y agoYeah, but both are very interesting, as are specific constraints that can be applied, like what's possible in 1D or 2D or 3D and how quantum mechanical phenomena enters into the limitations.
- ctdonath 8y agoHelps the discussion to bracket possibilities. If there's an absolute hard limit somehow, let people know so they don't assume it's possible to go further. I find this useful in discussing solar power: there is an absolute maximum of 1300 watts per square meter; most people don't know this and implicitly assume substantially higher is achievable.
- gjm11 8y agoThe amusing thing about the Bekenstein bound is that it's per millimetre squared, not per millimetre cubed. The amount of information you can pack into a given region of space scales like length^2, not length^3. For the sorts of scales human beings are interested in, of course, the Bekenstein bound is a long long way from being relevant, and what matters for us in principle is volume rather than area. (There are practical difficulties in using "substantially" 3-dimensional regions for storage, but they have nothing to do with the danger of the storage device turning into a black hole.)
- biggerfisch 8y agoThere is such a limit to areal density. The math involved dives into entropy and the planck length, but the short answer is that any information at a quantum level must be quantized in some form and the smallest possible quantization is the planck length squared, called the "planck area". reference: https://physics.stackexchange.com/a/2283 https://physics.stackexchange.com/a/2283
- bsamuels 8y agothis is probably a silly question, but why isnt the smallest possible quantization just planck length, or planck length cubed?
- eximius 8y agoI think they're talking about _area_ specifically.
- smilliken 8y agoThe idea is that our universe has three spatial dimensions, but only two are needed to represent a given volume of space. All the information is on the boundary surface. In other words, we live in a hologram.
- spiralx 8y agoThe holographic principle says that all of the information required to represent a 3-D volume is encoded on the 2-D surface of its boundary i.e. in one sense there is no difference between e.g. a black hole and its surface. https://en.wikipedia.org/wiki/Holographic_principle https://en.wikipedia.org/wiki/Holographic_principle
- spiralx 8y agoIt's actually 2x2 Planck lengths per bit, so 4 Planck areas. https://en.wikipedia.org/wiki/Bekenstein_bound https://en.wikipedia.org/wiki/Bekenstein_bound
- zwischenzug 8y agoWhat a coincidence I was reading Feynman's 'Plenty of room at the bottom' lecture just this morning! https://en.wikipedia.org/wiki/There%27s_Plenty_of_Room_at_the_Bottom https://en.wikipedia.org/wiki/There%27s_Plenty_of_Room_at_th...
- skykooler 8y agoTheoretically, you could store information in the spin state of every electron in an atom. For gold, for example, that would yield 79 bits per atom.
- ksec 8y ago>Hardrives are roughly 1Tb/in^2 in areal density right now. SSD's are a little better. I am pretty sure 1Tb is 1 Terabit/in^2. Here it is 138 Terabytes / in^2, or 1104 Terabit/in^2, hence the 1000 times difference. Not 100 Western Digital MAMR allows up to 4 Terabit/in^2, so the difference is now slightly closer to ~250x. Then there is Bit pattern media, which should get us to 10 Terabit/in^2. But it doesn't look like HDD manufacture are in any hurry, they will try to milk the market for as long as possible. The Total HDD market will fall to 50% of its peak volume sometimes next year or in 2020.
- epicureanideal 8y agoWhat's causing the drop in demand? Anyone know?
- ksec 8y agoFalling PC Shipment. Notebook transition to SSD. The move to cloud computing, where Cloud providers chooses higher capacity unit rather then slightly cheaper price per GB model. Obviously the TCO flavours the former on power and space usage.
- dekhn 8y agomaybe your peak volume numbers should be normalized by unit capacity.
- ksec 8y agoTrue. But but even if you had double the capacity at half the unit shipment, it would still have used half of the motor, half of the casing, assembly, heads etc..... In terms of business isn't exactly good.
- dekhn 8y agohard drive manufacture is economic- it's like oil, with volumes enough that there is a liquidity to the market. I would expect that the market will drive hard drive manufacturers to effectively zero profit. This is a good thing for everybody.