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Posts posted by SergUpstart

  1. 12 minutes ago, Genady said:

    To the contrary, we can and we do. 

    The exact modern definition, from the National Institute of Standards and Technology is: "The second, symbol s, is the SI unit of time. It is defined by taking the fixed numerical value of the cesium frequency ΔνCs, the unperturbed ground-state hyperfine transition frequency of the cesium 133 atom, to be 9192631770 when expressed in the unit Hz, which is equal to s⁻¹." (wiki)

    For a standard unit of distance you can take a distance that light covers in one standard unit of time.

    Are you sure that this frequency standard is absolute? Are you sure that if you move this caesium atom (like an atom of any other chemical element) to a point with a different gravitational potential, its spectrum will not shift?

  2. 4 minutes ago, Genady said:

    The box keeps its shape and size. The atoms of the material it is made of do not expand, distances between atoms do not expand as the universe expands. The walls of the box do not move relative to each other.

    E.g. the distances between far away galaxies increase, but the galaxies themselves do not grow as the universe expands.

    The thing is that we do not and cannot have absolute standards of distance and time. The distance between galaxies increases faster than the size of the galaxies themselves and we only see this difference. Therefore, we will not be able to notice the red shift of photons in the box because there is no absolute standard of frequency to compare with.

  3. 4 minutes ago, Genady said:

    Imagine a box with internal walls covered with mirrors. A light /photon bounces inside the box from mirror to mirror. The box is placed far away from gravitating bodies, somewhere in the homogenous and isotropic universe. As the universe expands, will the light inside the box redshift?

    Will be. As the universe expands, the dimensions of the mirror box will also increase. I.e., the walls of the mirror box are constantly moving in different directions, photons should experience the Doppler effect with each reflection from the walls of the box.

  4. Artificial intelligence in one of the district people's prosecutor's offices in Shanghai for the first time became the compiler of the text of the indictment, which will be presented to the criminal in court.

    This is reported by Economic News with reference to haggin.az

    According to the South China Morning Post newspaper, AI received prosecutorial skills after studying more than 17 thousand cases considered in the courts of Shanghai from 2015 to 2020. The "digital prosecutor" makes accusations with 97% accuracy, based on one thousand "characteristic features" that he identifies in court documents on specific criminal cases.

    "Artificial intelligence to a certain extent can replace prosecutors in the decision-making process, as well as assist them in drafting indictments, which will reduce their daily workload and enable prosecutors to focus on more important cases," the publication notes.

    According to the newspaper, the "digital prosecutor" is initially able to bring charges for eight of the most common crimes in Shanghai, such as credit card fraud, gambling, dangerous driving, intentional injury, obstructing authorities in the performance of official duties, theft, fraud. Scientists are confident that in the future AI will be able to bring charges for more high-profile crimes.

  5. Scientists at the Massachusetts Institute of Technology, Cardiff and Cambridge Universities have figured out what chemical reactions could make the clouds of Venus habitable.
    The fact is that ammonia found in the atmosphere of the planet in the 1970s is able to neutralize drops of sulfuric acid, writes MIT News. https://news.mit.edu/2021/habitable-venus-clouds-acid-neutralizing-1220
    And then there could be biological species similar to terrestrial ones. The scientists explained that ammonia turns acid into ammonium sulfite, which in itself can create an environment in the clouds of Venus suitable for life. 

    Scientists were prompted to conduct a study by mysterious anomalies in the clouds of Venus – such as small concentrations of oxygen, which should not be there.

  6. 33 minutes ago, CharonY said:

    As a whole, I see more elements in play that favour an intervention in a China-Tawan conflict as between Ukraine and Russia. In addition the stability in Taiwan also makes it difficult to justify a Russia-style takeover. 

    The majority of the population of Taiwan does not want Taiwan to join China, but the majority of the inhabitants of Crimea wanted to join Russia.

    21 minutes ago, iNow said:

    Biden and Putin speak today. My hope is much of this troop movement from Russia to Ukraine is little more than a shrewd negotiating tactic from Putin, but that seems hopelessly optimistic and a bit like fairy dust thinking to me. 

    The movement of Russian troops near the borders of Ukraine is pressure on Ukraine not to launch an offensive on Donetsk and Lugansk.

  7. 22 minutes ago, paulsutton said:

    While the west cuts military,  Russia / China seem to have been building theirs up.

    Russia has approved the defense budget for 2021-2023 — it was reduced by 10%. Despite this, it guarantees the combat readiness and development of the country's Armed Forces.

    Deputy Minister of Defense of the Russian Federation Tatyana Shevtsova told the newspaper Krasnaya Zvezda about this.


    At the same time, military salaries have been increased in Russia, so the cost of purchasing weapons will be reduced even more.

  8. On 12/5/2021 at 8:40 AM, iNow said:

    Intelligence suggests Russia is planning to invade Ukraine in January apparently with the intent to take it over. Likewise, China has been stepping up plans to seize Taiwan. Have been talking about it for years, but seem to sense more opportunity in todays global political climate.

    Should US respond if/when either of those two things happen? If so, how and for how long? Does your answer change if both events happen at the same time?

    And if Aliyev and Erdogan also seize Armenia

    Earlier, Aliyev had already stated that Yerevan belongs to Azerbaijan

  9. On 12/4/2021 at 10:05 PM, joigus said:

    Another thing is that ε0 is not really a constant of Nature. Rather, just an artifice in the choice of units for electric charge. Stick to Heaviside-Lorentz units and there's no ε0 . It disappears!

    It seems to me that a more important physical constant is 4 *Pi*G*epsilon0, which shows how many times stronger bodies with masses of 1 kg interact gravitationally stronger than two charges of 1 Coulomb at the same distance. The dimension of this constant is  Сoulomb^2/kg^2 that is, it does not depend on the distance scale.

  10. 2 hours ago, TheVat said:

    Ukraine, with its central location, and having major NG and mineral resources, and being one of the planet's major grain exporters, and having received some serious commitments from the US and European allies, and being headed towards NATO membership, might be a more significant bone of contention, and maybe even rise above our domestic catnip issues.  It will be ugly when it heats up.  But I'm not scanning the real estate ads in Auckland yet.  Maybe I should.  

    In 2014, Putin could have seized the whole of Ukraine, but limited himself to Crimea. Putin only needs the opportunity to export gas to Europe. He can send troops into Ukraine only in response to Ukraine's actions, which may be the offensive of Ukrainian troops on Donetsk or the blockade of Tiraspol.

  11. 41 minutes ago, A_curious_Homosapien said:

    I heard about fly wheel battery systems and after reading a bunch of articles and watching some videos about it I have an Idea. Basically the fly wheel looses it's rotational energy only due to friction(or am i wrong?), so if I we are able to eliminate all the friction forces by taking it to space where it won't take much energy to elevate it with magnets and also by creating vacuum, will I be able to create unlimited energy since the wheel will keep spinning for ever(or at least for drastically longer period than the current ones)?

    Even an ideal flywheel will lose energy if you take it away from it. So you won't get unlimited energy. And if you mean storing energy for an unlimited time, then a superconducting ring with a current or a vacuum capacitor is better.

  12. On 11/10/2021 at 10:00 AM, bangstrom said:

    Can you give us some examples where interactions between light and matter can't be explained as a wave. The photoelectric effect has been discussed and the discrete nature of photon termination can also be explained as a wave without recourse to the simplistic analogy of particle impact. I don't find either of these as convincing evidence for the particle nature of light or am I missing something?

    The sensitivity of the human eye allows detecting a stream of 100 photons, but the frog's eye can detect even single photons. Therefore, if you move away from the glowing flashlight in the void and darkness, a person at some distance will stop seeing the flashlight. But the frog will always see the flashlight, but from a certain distance the light of the flashlight will blink and the frequency of blinking will decrease with increasing distance.


  13. 1 hour ago, amshion said:

    The big bang theory is very vague, it doesn't explain how the matter was created to cause the big bang you would need energy but where did the energy come from. lets say this universe is a simulation, the universe that created our universe how was that universe created or is their a god but what created the god? in science matter cant be created by nothing it requires energy. 

    Matter and energy arise and disappear constantly in accordance with the Heisenberg uncertainty principle. So the origin of the universe is most likely a quantum effect. God is not needed for this.

  14. 7 hours ago, bangstrom said:

    I understand the evolution of the universe as a several billion year emergence from a gravity well with the BB at the very bottom

    Yes, and after BB, the universe rises in a gravitational well. This means that the red shift in the spectra of galaxies has not only a Doppler component, but also a gravitational one.

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