This idealization does not seems to be possible at all in the context of Maxwell's equations with pointlike particles.
Ciro Santilli believes it generally hurts more than it helps.
Especially when you can't even mention censored things to criticize them. You have to pretend they never existed. So people will forget about them, and do them again in the future.
Is implied by Gauss' law if Maxwell's equations: physics.stackexchange.com/questions/44418/are-the-maxwells-equations-enough-to-derive-the-law-of-coulomb
The "static" part is important: if this law were true for moving charges, we would be able to transmit information instantly at infinite distances. This is basically where the idea of field comes in.
Coulomb's Law experiment with torsion balance with a mirror on the balance to amplify rotations by uclaphysics (2010)
Source. And analogously for matter, appears in the de Broglie relations relating momentum and frequency. Also appears in the Schrödinger equation, basically as a consequence/cause of the de Broglie relations most likely.
Intuitively, the Planck constant determines at what length scale do quantum effects start to show up for a given energy scale. It is because the Plank constant is very small that we don't perceive quantum effects on everyday energy/length/time scales. On the , quantum mechanics disappears entirely.
A very direct way of thinking about it is to think about what would happen in a double-slit experiment. TODO think more clearly what happens there.
Defined exactly in the 2019 redefinition of the SI base units to:
The Taylor series expansion is the most direct definition of the expontial as it obviously satisfies the exponential function differential equation:
This is an extremely widely used technique as of 2020 and much earlier.
If allows you to amplify "any" sequence of choice (TODO length limitations) between a start and end sequences of interest which you synthesize.
If the sequence of interest is present, it gets amplified exponentially, and you end up with a bunch of DNA at the end.
You can then measure the DNA concentration based on simple light refraction methods to see if there is a lot of DNA or not in the post-processed sample.
Even Ciro Santilli had some contact with it at: Section "How to use an Oxford Nanopore MinION to extract DNA from river water and determine which bacteria live in it", see: PCR!
One common problem that happens with PCR if you don't design your primers right is: en.wikipedia.org/wiki/Primer_dimer
Sometime it fails: www.reddit.com/r/molecularbiology/comments/1kouomw/when_your_pcr_fails_again_and_you_start/and a comment:
Nothing humbles you faster than a bandless gel. One minute you’re a scientist, the next you’re just a pipette-wielding wizard casting spells that don’t work. Meanwhile, physicists are out there acting like gravity always behaves. Smash that upvote if your reagents have ever gaslit you.
PCR = Pray, Cry, Repeat
What a material:
- only exists in trace amounts in nature,but it can be produced at kilogram scale in breeder reactors
- it is only intentionally produced for one application, and one application only basically: nuclear weapons
However, there is nothing in the immediate definition that prevents us from having a ring instead, i.e. a field but without the commutative property and inverse elements.
The only thing is that then we would need to differentiate between different orderings of the terms of multivariate polynomial, e.g. the following would all be potentially different terms:while for a field they would all go into a single term:so when considering a polynomial over a ring we end up with a lot more more possible terms.
If the ring is a commutative ring however, polynomials do look like proper polynomials: Section "Polynomial over a commutative ring".
One of the main reasons why physicists are obsessed by this topic is that position and momentum are mapped to the phase space coordinates of Hamiltonian mechanics, which appear in the matrix mechanics formulation of quantum mechanics, which offers insight into the theory, particularly when generalizing to relativistic quantum mechanics.
One way to think is: what is the definition of space space? It is a way to write the wave function such that:And then, what is the definition of momentum space? It is of course a way to write the wave function such that:
- the position operator is the multiplication by
- the momentum operator is the derivative by
- the momentum operator is the multiplication by
physics.stackexchange.com/questions/39442/intuitive-explanation-of-why-momentum-is-the-fourier-transform-variable-of-posit/39508#39508 gives the best idea intuitive idea: the Fourier transform writes a function as a (continuous) sum of plane waves, and each plane wave has a fixed momentum.
Bibliography:
PostgreSQL feels good.
Its feature set is insanely large! Just look at stuff like: stackoverflow.com/questions/1986491/sql-split-string-by-space-into-table-in-postgresql/1993058#1993058
If Oracle is the Microsoft of database, Postgres is the Linux, and MySQL (or more precisely MariaDB) is the FreeBSD (i.e. the one that got delayed by legal issues). Except that their software licenses were accidentally swapped.
The only problem with Postgres is its name. PostgreSQL is so unpronounceable and so untypeable that you should just call it "Postgres" like everyone else.
- 2024 www.uktech.news/foodtech/alternative-meat-research-centre-20240829A research centre examining the implementation of alternatives to meat, backed by £38m, will be launched by the University of Leeds.
- 2024 techcrunch.com/2024/08/04/even-after-1-6b-in-vc-money-the-lab-grown-meat-industry-is-facing-massive-issues/ "Even after $1.6B in VC money, the lab-grown meat industry is facing 'massive' issues"
- www.reuters.com/markets/commodities/hoxton-farms-raises-22-million-cultivated-animal-fat-2022-10-20/ Hoxton Farms, cultured animal fat
Ubuntu 21.10 has a certain default level of logging by default to:but it does not log everything, only/mostly errors it seems.
/var/log/postgresql/postgresql-13-main.logSetting:under:and then restarting the server:just works.
log_statement = 'all'/etc/postgresql/13/main/postgresql.confsudo service restart postgresqlRealtime monitoring for long queries instead: stackoverflow.com/questions/8597516/app-to-monitor-postgresql-queries-in-real-time
When using SQL REPEATABLE READ isolation level and SQL SERIALIZABLE isolation level, concurrent transactions may fail with a serialization failure, and then you might need to retry them. You server code or your ORM must always account for that.
Related questions:
- stackoverflow.com/questions/7705273/what-are-the-conditions-for-encountering-a-serialization-failure
- stackoverflow.com/questions/59351109/error-could-not-serialize-access-due-to-concurrent-update
- stackoverflow.com/questions/50797097/postgres-could-not-serialize-access-due-to-concurrent-update/51932824
Encryption algorithms that run on classical computers that are expected to be resistant to quantum computers.
This is notably not the case of the dominant 2020 algorithms, RSA and elliptic curve cryptography, which are provably broken by Grover's algorithm.
However, as of 2020, we don't have any proof that any symmetric or public key algorithm is quantum resistant.
Post-quantum cryptography is the very first quantum computing thing at which people have to put money into.
The reason is that attackers would be able to store captured ciphertext, and then retroactively break them once and if quantum computing power becomes available in the future.
There isn't a shade of a doubt that intelligence agencies are actively doing this as of 2020. They must have a database of how interesting a given source is, and then store as much as they can given some ammount of storage budget they have available.
A good way to explain this to quantum computing skeptics is to ask them:Post-quantum cryptography is simply not a choice. It must be done now. Even if the risk is low, the cost would be way too great.
If I told you there is a 5% chance that I will be able to decrypt everything you write online starting today in 10 years. Would you give me a dollar to reduce that chance to 0.5%?
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