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Sensei

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Posts posted by Sensei

  1. @Eise phileo + sophia = love of wisdom, in the distant past, with modern redefinition of this word, it is very hard to agree with it..

    Many old, good-looking words have been redefined in such a way that they no longer have the same meaning as they did two or three thousands years ago..

    ps. The marketing staff is even better at disgusting people for certain words.. ;)

     

  2. On 2/18/2024 at 9:26 PM, Capiert said:

    The devil is in the detail(s).

    Michelson was biased and you are biased too. Other people responding here are also biased because they now take what they learned from books as dogma. Not many have equipment at home to perform experiments by themselves. It's hard to get past dogma, or even imagine that you can get past dogma. That's why the best results (discoveries) come from young students who have nothing to lose in the scientific world. Once someone gets a reputable name, it is very difficult to enter a controversial topic and potentially lose all respect.

    If you bought the required equipment and started doing physical experiments, the conversation with you would be much more fruitful. It is not very expensive. An investment of a few hundred to a few thousand dollars. Much less than the time spent on the discussion.

  3. On 2/18/2024 at 2:05 PM, Capiert said:

    I DON'T understand that sentence.
    Could you please restate it, differently?

    No single particle has a shape..

     

    The probability density function is not a shape..

     

    On 2/18/2024 at 2:39 PM, Capiert said:

    So really your data
     is about interactions;
     & NOT particles.

    We learn about particles (molecules, or macroscopic objects) from observations and the interactions they caused on other objects..

     

    On 2/18/2024 at 2:39 PM, Capiert said:

    But you have the nerve to say "particles", instead;
     so that people might understand
     (at least the substitute (name)).(?)

    If/when photon is detected it disappears i.e. it is absorbed..

    On 2/18/2024 at 2:39 PM, Capiert said:

    What is Lepton number?

    Beyond that?

    https://en.wikipedia.org/wiki/Lepton_number

     

    On 2/18/2024 at 2:39 PM, Capiert said:

    That sure sounds like hit & mis(sed).
    It does leave me doubting a bit.
    E.g.
    You assume
     hitting the atom(s)
     dead on 0°
     at their center
     when measuring
     their reflected angle?
    & with thermal motion.

    How do you know?

    That is surely bound
     to fail!

    It's NO wonder
     your data
     does NOT (always) corelate
     with real sizes.

    It's a MESS!

    If you shoot at a flying birds with a shotgun, you will shoot several birds (I don't recommend this, it's just an analogy). If you shoot enough bullets, you should find out the size of the birds you tried to kill by simply looking at which bullets missed the target. The same is true for particles that can be placed at rest, in their rest frame, such as a proton or the nucleus of another element. The number of bullets is counted in the millions or billions. So you can get a pretty good image if you hit something and it is reflected or you miss..

     

    We find out about the existence of one particle by hitting it with another particle, which we can control, e.g. a beam of photons, a beam of electrons, a beam of protons, etc. Unknown target hit by known source and observation what happens. e.g. a new beam of photons from that target (e.g. spectroscopy https://en.wikipedia.org/wiki/Spectroscopy )

     

    If you have a better idea, you should start a new thread. But you'd better check it out for yourself. That's what scientists do, first they experiment, then they talk. You seem to be doing the opposite.

     

    On 2/18/2024 at 2:39 PM, Capiert said:

    & with thermal motion.

    ..one (you) can make experiment at ~ 0 K..

     

    Did someone forbid you to do physical experiments?

    On 2/18/2024 at 6:05 PM, Capiert said:

    I guess what confuses me there
     is 2 answers
     (in 1 sentence).

    Are you saying:
     a photon
     does NOT have a shape.
    (But)
     Only a (single) particle
     has a shape.
    ?

    E.g. (It has)
    None (=NO shape), a single particle has (a) shape
     ((but) NOT a photon).

    I said that neither the photon, electron, positron, neutrino, antineutrino, etc. have a shape...

     

    On 2/18/2024 at 6:38 PM, Capiert said:

    Maybe, we could give it (=Intensity)
     the units
     for the
     (average_)momentum squared
     per area, or per volume

     so it would be some kind
     of density,
     as
     kilograms_squared
     meters_squared
     per
     second_squared
     per meters_
    (squared or else )cubed.?

    By saying "What is the unit of intensity?" I wanted to point out that intensity has already defined units that don't match your..

    https://en.wikipedia.org/wiki/Intensity_(physics)

    "In physics, the intensity or flux of radiant energy is the power transferred per unit area, where the area is measured on the plane perpendicular to the direction of propagation of the energy."

     

    On 2/18/2024 at 8:15 PM, swansont said:

    You demand that we spoon-feed you information. And you’re rude in doing so.

    ..no one is forced to do so..

     

     

     

  4. 24 minutes ago, Silverstreak said:

    I know that there is Einstein's equation that relates energy and matter. However, I was curious about what would occur if there was a universe where light didn't exist. Assuming that's even possible, would there be any relationship between matter and energy or would they be completely separated? Would they fail to exist in such a place? Thank you for indulging my curiosity.

    The whole subject is so deep, I don't even know where to start..

     

    How about pair production?

    https://en.wikipedia.org/wiki/Pair_production

  5. 6 hours ago, swansont said:

    When did he say this? As MigL said, context matters.

    Also, are these exact quotes, or are you changing the message by paraphrasing?

    In 2014:

    https://www.forbes.com/sites/russellflannery/2014/09/09/chinas-rise-isnt-a-threat-to-the-u-s-former-president-jimmy-carter-says/?sh=217a83ee235b

     

    "China’s rising success in the world isn’t a threat to the United States, former U.S. President Jimmy Carter said in a speech in Shanghai to mark the 35th anniversary of the establishment of diplomatic ties between the two countries this year."

     

  6. 4 minutes ago, StringJunky said:

    primarily because tv manufacturers only issue software updates for two or three years.

    ..this is the case with any device..

    My primary phone ATM was made in 2019. It has Android v10 built-in. It wont be updated to v11, v12, v13 or v14 etc.

    I can do it myself. LineageOS or AOSP or Kali nethunter.. and have Android v14 or my own OS.

     

  7. 5 minutes ago, TheVat said:

    I've heard this, don't know if that's a real thing.  I opted not to buy a so-called Smart TV due to the suspicion about them and the mics.  Five seems like a lot, though!  🙂

    Simply, don't plug TV to the Internet.. Make sure there is no open WiFi around you etc. Don't let TV to use your WiFi hotspot created by phone etc. etc. If you do so, change password on the phone every time you are done with the TV.

    ps. I know a person who cuts the circuit connections on a Visa debit card that allows NFC/RFID transmission....

     

  8. 14 minutes ago, StringJunky said:

    Some TVs have 5 or more microphones in them, listening for keywords. Ditto other devices.

    You have AOSP. You can download, install, compile, upload your own OS, and modify it the way you want it to work.. ;)

     

    5 minutes ago, exchemist said:

    Do you know that ? I should have though that could be grounds for a lawsuit for invasion of privacy. Can I read about this somewhere? (As it happens, I don't have a TV, but I think it would be scandalous if true.)

    Are you living under a rock?

    https://www.google.com/search?q=siri+listens+to+everyone

     

    Say "Hey, Siri" or "Hello, Google," etc.

    If the app is open, the microphone has to listen to everything to detect your words.

     

    https://www.google.com/search?q=siri+data+leak

     

  9. Ads bring money to the site owner. Scientists are smart enough not to click on most of them. Therefore, the return on investment is zero or marginal. So people who own a website will try to make the ads more aggressive or force people to click them by mistake, etc. etc. tactics are used.

     

    Streaming sites such as YouTube display 5-second ads before allowing you to skip. Some other streaming sites require 30-second views, or I even know of one that requires 5 minutes long ads watching. It is so aggressive that it detects if the user has clicked on another browser window and pauses the video ads, until you finish 5 minutes...

     

  10. 5 minutes ago, TheVat said:

    I automatically scrub my browsing info (cache, cookies, etc) so the ads are generally wild and incorrect guesses.  As the OP indicated, I object to the quantity and the format which is used on my Chrome device.

    Check if it is possible and install LineageOS on it.

    https://lineageos.org/

    If you're using the Chrome browser on an Android device, don't expect them to chop down the tree they're sitting on.

     

  11. 13 hours ago, TheVat said:

    Tired of harassment-level ads that constantly drop over the page one is trying to navigate to.  Is there a way to get some feedback to @blike and go back to the usual banner ads or other formats one can scroll past?  Does anyone really think they're going to sell a product by shoving it in our cyber-faces over and over?  I would think there is an inverse relationship between rudeness of ads and sales generated.  SFN is better than this. 

    And no, I don't want to change my wifi provider, thanks.

    The ads are personalized. Take a screenshot of what ads you are talking about.. Are you complaining about their quantity or quality?

    When I open SFN from my Linux desktop, logged in or not, I don't see any ATM ads.

    When I open SFN from my cell phone, I see some ads.

    On neither of them am I logged into either a Google account or an Apple account.

  12. 14 hours ago, Capiert said:

    If that is because it is NOT round
     then please describe
     this real particle's shape.
    I.e. Photon.

    None a single particle has the shape..

     

    If you have many particles bound together by forces (e.g. proton, meson, exotic atom), they have what can be called shape ("the probability density function of finding a particle in a certain place at a certain time").

     

    Look. particles mostly pass through each other undetected. Hence the Geiger-Marsden experiments, also known as the Rutherford gold foil experiment.

    https://en.wikipedia.org/wiki/Geiger–Marsden_experiments

    When there is a lot of them, e.g. thick layer of Gold, particles eventually hit something and are being reflected. But some of them pass through it like they were flying through nothing..

    Macroscopical equivalent is a swarm of meteors passing through the solar system.. A collision with some planet occurs after billions of years.

     

    If you have macroscopic object with billions of billions particles e.g. ball, it will hit the wall, and being reflected by it, there is billions of billions particles in the ball, and there is billions of billions of particles in the wall which interact.

    If we have a single particle and a single "target," the chance of hitting and interacting is extremely low.

  13. 1 hour ago, Capiert said:

    OK. That's a good place
     to start.

    If you have a (single) photon
     with a wavelength
     of 21 cm,

    It is relative. The one observer will detect it as 21 cm, the other might it detect as 42 cm (red shifted), the other might it detect as 10.5 cm (blue shifted). Actually any wavelength. Because in Special Relativity you have no absolute wavelengths..

    https://en.wikipedia.org/wiki/Redshift

    https://en.wikipedia.org/wiki/Redshift#Blueshift

     

    1 hour ago, Capiert said:

    what does it look like?

    Is it round like a ball?

    None a single particle has the shape..

     

    1 hour ago, Capiert said:

    E.g. what is its diameter?

    Such questions have no sense..

    Particle is detected if it interacts ("hits") the other particle. If it hits it, it transfers some physical quantity on the second particle. Therefore we know there was interaction..

     

    The diameter of an atom can be "measured" because scientists use the flux of other particles toward the nucleus. If these are reflected, the "diameter" of the multi-particle entity, called the "nucleus," can be measured by the angles at which the initial particles were reflected.

    It is called cross section.

    https://en.wikipedia.org/wiki/Cross_section_(physics)

    The different isotopes have different cross sections.

     

    "If a poacher shoots birds with a shotgun, he will eventually shoot any bird.."

     

    26 minutes ago, Capiert said:

    That looks (a bit) like you are avoiding my question Sensei.
    We KNOW we are dealing with a wave,
     thus it has a (pretty obvious) wave_"length".

    But I did NOT ask that.

    I asked what was the wave "on".

     

    The wavelength is a property of the particle. Its (kinetic) energy can be mentioned instead of wavelength and get the same results.. e.g. the beam of electrons in vacuum with kinetic energy of 100 keV has similar effects on the matter as beam of photons with 100 keV. e.g. electrons in the matter will be excited and/or ejected (with the exception that other physical quantities such as Lepton number, must be preserved, so electron gives its kinetic energy, and is not disappearing (is not absorbed) ).

    Instead of saying "green photon" or "photon with a wavelength of 532 nm," you can say "photon with an energy of 2.33 eV." It's all the same.

  14. Quote

    How do scientists explain RF waves traveling, without a medium?

    Philosophy is a pseudoscience. Physics is a real science. Too often you ask philosophical questions.. ask physical questions, such as "how to measure the speed of something", "how to measure some physical quantity", etc., and you will get the right, truthful answers..

     

    1 hour ago, Capiert said:

    As far as I know
     water_waves travel

    ..one water molecule hits another molecule, which hits another molecule, and there is a momentum transfer between them in all directions, they hit something, while molecule remain at place (plus, minus, a little margin of tolerance (in global scale) )..

    1 hour ago, Capiert said:

    Radio_particles? (Radions?)

    They are called photons..

     

  15. 1 hour ago, chenbeier said:

    Why the people in Japan afraid to get the Tritium water from Fukoshima into the sea?

    It is pretty simple. If you drink such water, Tritium (with half-live 12.3y) becomes part of your body instead of Hydrogen, and decays inside of your body, destroying your cells and/or the DNA of which it is a part.. If fishes or sea plants are contaminated by it, and you, or animal will drink it, or eat fish, you will be contaminated indirectly..

    https://www.google.com/search?q=tritium+contamination

     

  16. 25 minutes ago, KJW said:

    Do beta processes (any type) emit gamma radiation?

    Beta decay can cause gamma radiation if the nucleus is not in the ground state and must return to the ground state.

    https://en.wikipedia.org/wiki/Gamma_ray#History_of_discovery

     

     

    Beta decay plus will cause positron emission, so it will eventually be annihilated, and gamma rays will also be produced..

  17. 10 hours ago, ALine said:

    Is there a metal out there you can bombard with electrons to get gamma radiation?

    X-rays and gamma rays are human-made classifications. They overlap with frequencies/energies. Classically, x-rays are photons emitted by electrons transitioning to a lower and/or to ground state of an element, and gamma radiation is emitted by an excited nucleus transitioning to a lower and/or to ground state. Sometimes X-rays have higher energy than gamma radiation, usually they have lower. To say more you need to know the number of protons in the nucleus and the atomic mass.

    If a particle strikes a nucleus with a kinetic energy higher than 1.022 MeV, production of an electron-positron pair occurs, ending in annihilation, which produces gamma rays..

     

  18. 4 minutes ago, Moontanman said:

    exactly where in the natural environment would you expect to see such high energy gamma rays?

    ..space.. which is.. almost. everywhere..

    https://www.google.com/search?q=gamma+ray+dectector+on+the+earth

     

    Gamma ray detectors.

    https://en.wikipedia.org/wiki/Oh-My-God_particle

    "The Oh-My-God particle was an ultra-high-energy cosmic ray detected on 15 October 1991 by the Fly's Eye camera in Dugway Proving Ground, Utah, United States.[1][2][3] As of 2024, it is the highest-energy cosmic ray ever observed.[4] Its energy was estimated as (3.2±0.9)×10^20 eV (320 exa-eV). The particle's energy was unexpected and called into question prevailing theories about the origin and propagation of cosmic rays."

     

    https://en.wikipedia.org/wiki/Ultra-high-energy_gamma_ray

    "Ultra-high-energy gamma rays are gamma rays with photon energies higher than 100 TeV (0.1 PeV)."

     

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