inlineint

The statement about detecting a single photon by an eye is new (and possibly contradictory), but detection of a very few number of photons by human eye is not a new thing. Cherenkov radiation[1] was discovered by observing a very small number of photons (actually only a few of them) in short time interval by eyes.

The experiments were conducted this way because there were no sensitive enough photodetectors in 1930s, so the eyes were the most sensitive available tool for this kind of experiments. Eyes of a physicist were prepared to the experiments by being in complete darkness for a few hours before the measurements. Description of the experimental procedure can be found here[2].

[1] https://en.wikipedia.org/wiki/Cherenkov_radiation

[2] http://iopscience.iop.org/article/10.3367/UFNe.0179.200911c....

But don't quantum measurements appear only to our (classical) perception? If someone (probably not in our Universe i.e. someone who doesn't interact with our Universe in any physical way) hypothetically able to write down the full Hamiltonian of our Universe (assuming that quantum gravity theory exists, so that is possible) then there is no external to this Hamiltonian "measurement devices", so wavefunction of the Universe does not collapse and the time evolution of Universe is reversable as soon as you can just multiply time to -1 in evolution operator.

But I don't understand why do they talk about time reversability of physical systems and don't mention CPT symmetry[1]? Standard model is not actually time symmetrical, but you one should also reverse charge and reflect spatial coordinates to obtain symmetry after time reversal because there are violations of CP symmetry [2].

[1] https://en.wikipedia.org/wiki/CPT_symmetry

[2] https://en.m.wikipedia.org/wiki/CP_violation

So do you mean that if my customer consume resources for let's say $10 then I charge that customer immediately and if the payment is declined I stop serving that customer? And do the same after next $10 consumed?

I didn't think about fraud yet, but thank you for the link.

It appears in some quantum field theory calculations, in particular for Casimir Effect.

In simple words Casimir Effect consists of a force that emerges between two conductor planes that are parallel to each other. The force is proportional to sum of energies of all possible standing electromagnetic waves between the planes. In calculations for this force a divergent series of sum of all natural numbers (or their powers) appears and physicists use 1 + 2 + ... = -1/12 to calculate it (or continuation of zeta function in other points if appropriate).

https://en.wikipedia.org/wiki/Casimir_effect#Derivation_of_C...

and

https://en.wikiversity.org/wiki/Quantum_mechanics/Casimir_ef...

In Russia there was all year DST since 2011 until 2014 (https://en.wikipedia.org/wiki/Time_in_Russia#2011_zone_bound...)

It was frustrating in December when Sun rose at 9.30am while first lecture in my university was scheduled to 9am.

Can you briefly describe technology/physical principles that power your VR suit?

I'm not able to see it on the website, maybe I'm just not looking good enough.

    $ pip show tensorflow theano
    
    Name: tensorflow
    Version: 0.7.1
    ...
    Requires: six, protobuf, wheel, numpy
    ---
    Name: Theano
    Version: 0.8.2
    ...
    Requires: six, scipy, numpy

You are right that arithmetic in both of them is not written on Fortran, but the packages do use NumPy as you can see in the pip output.

Yes, NumPy depends on BLAS/LAPACK libraries which are written on Fortran. In turn TensorFlow and Theano which used for implementation of most state of the art deep neural networks depend on NumPy, so Fortran is still alive and gearing such modern research.

There is no such Russian root word, so the name is English.

The robot seems to be developed especially for street promotions: http://en.promo-bot.ru/

And it contains Docker files in the source tree so you can just run it in container on any distribution.

Did you try to build it on Mac with GCC from Homebrew?

How much RAM do you need?

I can recommend SuperMicro boards but it's just a guess because it's better to know what exactly do you want.

I stated that I want to use numba, and it's a pain to install it from pip because a lot of system-wide dependencies have to be installed.

But isn't it much better than waste of the best minds for inventing more and more destructing weapons like it was in the twentieth century?

One qubit could hold 0 and1 simultaneously and perform some operations/calculations on it simultaneously.

Two (entangled) qubits could hold 00, 01, 10, 11 simultaneously and perform calculations on these four values simultaneouslty.

...

100 (entangled) qubits could hold 2^100 distinct values simultaneously and perform calculations on them simultaneously.

That's the basic idea. The problem is keeping entangled state that's becomes harder and harder as number of entangled qubits grows.

Also there are limitations in extracting of calculations results from system of qubits, so not all algorithms can be speed up on quantum computers (but e.g. integer factorization can).

What does mean the name of the site?

> that is always running and predictably costs $120/yr.

And predictably won't earn you magnitude more than $120/yr.

Some of third party modules (from https://www.nginx.com/resources/wiki/modules/) require patching, moreover if you want to just add a third party module to nginx you should recomplile nginx with configure flag --add-module=<directory> pointing to the module directory because nginx doesn't support dynamic loading of modules.

Ordinary computer can't model even a small quantum system exactly in finite time because it has to deal with infinite-dimension matrices to do it. In other hands, quantum computer could model any quantum system of the same size by one-to-one mapping of degrees of freedom. So you could build a quantum computer that just models your computer and do anything you could do on your ordinary computer on the quantum one.

If you are interested in the subject try to read this book http://www.amazon.com/Programming-Universe-Quantum-Computer-... (you can skip the parts about the Universe as quantum computer because they are controversial and a kind of metaphysics, just read a few first chapters to pick up the idea of quantum computations).

Thank you!

Basically I'm looking for an idea what to do, because I'm not sure that if I pick it myself it would be easy enough for me and interesting in the same time.

Only on quantum computers of sufficient size. And we are far from having idea about how to actually build them.

Yes, you are right. Each of these nanoparticles should also radiate heat radiation or heat the environment near it in other way, but it is not clear from the citation.

You are talking more about the first low of thermodynamics (conservation of energy law) than the second. The problem is that the processes you described radiate heat, but it is not explicitly stated that the process of combining of a few photos with low energy to photons with high energy does the same.

It is possible because the temperature of a photovoltaic cell is lower than the temperature of red light radiation, so the entire system radiates both higher-energy photons (blue light) and lower-energy photons (infra-red heat radiation).

The expression can't be an equality, otherwise it is possible to use such particles to transmit heat from a radiating black body with lower temperature to a radiating black body with higher temperature using a filter from these particles.

Thank you for detailed answer. I didn't know about the frameworks you listed except tensorflow.

Btw do you know anybody who use Julia for this?

> Now, however, other types of nanolight are on the rise. Some have a rare ability to absorb lots of low-energy photons and combine the energy into a handful of high-energy photons

Doesn't it violate the second law of thermodynamics?

It's fascinating.

Could anybody answer what programming language is most likely to be used for development of this kind of systems? I haven't found information about it in the paper.

It looks great. I think I will use it in my hobby projects instead of Bootstrap.

Read Think Bayes from the author of Think Stats.