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Physicists Made An Unprecedented 53 Qubit Quantum Simulator (vice.com)
Two teams of researchers have published papers [1, 2] in the journal Nature detailing how they were able to create unprecedented quantum simulators consisting of over 50 qubits. The University of Maryland team and National Institute of Standards and Technology team -- the two teams behind one of the two new papers -- were able to create a quantum simulator with 53 qubits. Motherboard reports: Quantum simulators are a special type of quantum computer that uses qubits to simulate complex interactions between particles. Qubits are the informational medium of quantum computers, analogous to a bit in an ordinary computer. Yet rather than existing as a 1 or 0, as is the case in a conventional bit, a qubit can exist in some superposition of both of these states at the same time. For the Maryland experiment, each of the qubits was a laser cooled ytterbium ion. Each ion had the same electrical charge, so they repelled one another when placed in close proximity. The system created by Monroe and his colleagues used an electric field to force the repelled ions into neat rows. At this point, lasers are used to manipulate all the ytterbium qubits into the same initial state. Then another set of lasers is used to manipulate the qubits so that they act like atomic magnets, where each ion has a north and south pole. The qubits either orient themselves with their neighboring ions to form a ferromagnet, where their magnetic fields are aligned, or at random. By changing the strength of the laser beams that are manipulating the qubits, the researchers are able to program them to a desired state (in terms of magnetic alignment).
According to Zhexuan Gong, a physicist at the University of Maryland, the 53 qubits can be used to simulate over a quadrillion different magnetic configurations of the qubits, a number that doubles with each additional qubit added to the array. As these types of quantum simulators keep adding more qubits into the mix, they will be able to simulate ever more complex atomic interactions that are far beyond the capabilities of conventional supercomputers and usher in a new era of physics research. Another team from Harvard and Maryland also released a paper today in which it demonstrated a quantum simulator using 51 qubits.
According to Zhexuan Gong, a physicist at the University of Maryland, the 53 qubits can be used to simulate over a quadrillion different magnetic configurations of the qubits, a number that doubles with each additional qubit added to the array. As these types of quantum simulators keep adding more qubits into the mix, they will be able to simulate ever more complex atomic interactions that are far beyond the capabilities of conventional supercomputers and usher in a new era of physics research. Another team from Harvard and Maryland also released a paper today in which it demonstrated a quantum simulator using 51 qubits.
For uninitiated, does it mean some of our KeyEx methods that rely on factorization are about to get broken?
Scott Aaronson, a prominent quantum computing expert made comments about some very similar work that is relevant https://www.scottaaronson.com/blog/?p=3512. The short summary is that we should expect people to continue to push up how many qubits can be practically simulatable. But that sort of improvement through clever tricks and the like doesn't really do much to address the more interesting issue of quantum supremacy https://en.wikipedia.org/wiki/Quantum_supremacy, whether there are problems that a quantum computer can solve that a classical computer practically cannot. Note that the "practically" in the previous sentence is really important. Everything a quantum computer can do a classical computer can do with exponential slow down; standard conjectures essentially amount to saying that a classical computer cannot do any better than that.
How much qubits do they need to break RSA?
Well, it *CAN* and it *CAN'T*...
53 qubits ought to be enough for anybody.
PlanetVulkan.com
And lining them like a group of balls on a billiard table. But even if this idea comes true, to being a real regular computer that works on your desktop. Will the Net Neutrality put all this tremendous work in vain?? It's like putting a Tesla that will go 0 to 60 in three seconds. On a road that only goes 10 miles an hour.
I wonder if you can use this same technology to employ line of sight. House to house transmission of data? That would be cool! Game with your neighbors!
That would give them a decent start on building an arq.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
Now THAT is a classic I have not seen in some time.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
They can bubble sort faster than 'classical' computers. Only sometime the results won't be sorted properly, and often it will be slower than qsort.
Quick take my money, I'm gullible!
How did this get modded up? Quantum computers are not supposed to give results instantly. Even general purpose quantum computer algorithms are expected to not return the best optimization every time, which is why they are proposed as good for problems that are easy to verify but hard to search. E.g. Shor's algorithm for factorization includes the possibility of re-running the algorithm when verification of the result on classical computer fails.
I peeked inside. It can't now. :(
Now that's something to be really excited about!
How is it circular? This is no different than saying, "A hydraulic computer is not modeling water flow without water, but is an analog computer using water to model other things."
GGP said this uses no actual quantum states. GP says that is flat out wrong: This computer uses qubits, but is not a general purpose quantum computer. It is the same difference as between a general purpose cpu and a fixed logic circuit that does one thing, but still uses bits.
If that seems circular, then it is because your reading comprehension has been impaired by your preoccupied with where people stick their genitalia.
Others have pointed out that it should be able to break a 21-bit key (half the number of qbits).
According to John Martinis' (from Google) invited talk to this year's Crypto 2017, building a quantum computer with as many qubits as possible might be good for getting into the headlines, but for being otherwise useful, the qubits' error rate and how long they stay stable is as important. For current sizes 1% error rate might be OK, but as quantum computer become bigger they have to drop below 0.1% for being able to use error correction.
Thanks to error correction there is an important distinction to make between physical (before error correction) and logical (after error correction) qubits. They guys and gals building quantum computer offer physical qubits, but the theorists use logical qubits. If you can factor with few thousand logical qubits, you need a quantum computer with 100,000s to 100 millions physical qubits (how many depend on the error rate).
Comment removed based on user account deletion
Quantum simulators are a special type of quantum computer that uses qubits to simulate complex interactions between particles. Qubits are the informational medium of quantum computers, analogous to a bit in an ordinary computer. Yet rather than existing as a 1 or 0, as is the case in a conventional bit, a qubit can exist in some superposition of both of these states at the same time.
I love how quantum people love writing stuff like this, because if you don't already know exactly what it means, it won't do diddly dick to help you clarify what a quantum computer is anyway.
All I really want to know is when can they laser-cool my beer?
According to this, 53 qubits can simulate 1 gram of DNA: https://www.quora.com/Quantum-...
-Myke
quantum teleporation
Stop. Go directly to jail. Do not pass GO. Do not collect $200.
Teleportation violates causality. Stop using that fucking word for things that are absolutely not teleportation.
FYI 53 cubits is 0.120454 furlongs
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
Is there any way to use a 53 qubit quantum computer to crack a longer key faster than a classical computer but slower than a quantum computer with more bits? I.e split Shor's algorithm up into multiple stages?
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
Well im not happy with the word the physicists have chosen either, but this is actually established terminology. It refers to the ability to transfer a qubit by actually transfering 2 classical bits, provided the two parties have preshared an EPR entangled pair of qubits.
Teleportation is instantaneous spatial transference.
Anything else (such as encoding, destroying and rebuilding) is not teleportation.
Teleportation is impossible without violating causality. And that's why it's important to keep the definition clear, just as Tachyons are not merely "really fast particles".
Besides, if violating causality is impossibly, why reserve and lock away a word to only be used to describe an impossible process, when a slightly broader use is actually applicable to something that exists?
Precisely because there's a hard, definitive line between what's possible and what isn't (as far as we know).
It's the same reason Tachyons have a name that isn't bastardized and used for other random fast particles.