• =?UTF-8?Q?Re=3A_Want_to_prove_E=3Dmc=C2=B2=3F_University_labs_shoul?= =

    From Paul B. Andersen@21:1/5 to All on Wed Nov 20 22:27:04 2024
    Den 20.11.2024 01:47, skrev rhertz:
    To make things more realistic and feasible, I changed the material of
    the cavity for aluminum, which has a reflectivity of 99%. I figure out
    the weight of each cavity as being 2 grams.

    The aluminum coating on the inside has, on purpose, an irregular surface
    in the order of nanometers, so the laser beam will disperse in each
    bounce.

    I suggest that the laser output be dispersed by a vibrating lens, prior
    to its entry to the cavity. In this way, the beam will be continuously dispersed. Even more, 4 or 5 different lasers (total power = 5 W) be
    placed in such a way that they cover the entire volume of the cavity, accelerating the process of energy spread in its volume.

    New calculations, using aluminum:



    h = 6.62607E-34    J.sec
    λ = 5.50E-07 m
    c = 3.00E+08 m/s
    E(photon) = 1.21E-48 Joules

    5 W = 5 Joules/sec = 4.12E+48 photons/sec
    5 Joules/hour = 1.48E+52 photons/hour

    Inner surface of cavity = 7.85E+03 mm²
    Area of laser spot  =      3.14159 mm²
                         2,500    spots

    Time between hits =     3.333E-10 seconds (10 cm avg. trajectory)
                        3.00E+09 bounces/sec

    photon hits/sec in the cavity = 1.37E+39
    photons hit/sec x spot =     5.4879643E+35

    Reflectivity with aluminum =     99.0%
    photons reflected/sec x spot =     5.4330846E+35
    photons absorbed/sec x spot =     5.49E+33

    energy lost/sec x spot =     6.67E-15 J
    energy lost/sec in the cavity = 1.67E-11 J
    energy lost/Hr in the cavity =     6.00E-08 J
    energy lost/Hr in the cavity =     1.43E-08 cal/Hr


    energy lost in 72 Hr, in the cavity =     1.032E-06 calories

    Even if I made errors in the order of 1,000:1, still the heat absorbed
    is insignificant (0.00103 calories).




    AS A REFERENCE:

    1 calorie is the heat that raises 1"C to one gram of water.

    With this new arrangement and materials, proving/disproving E=mc² should
    be much easier and cheap. The weight increment is in the order of 9 μN (1.0368 μgrams of MASS) can be measured with EM balances of $ 10,000.

    Its remarkable that you (and others) don't understand how hopeless
    this is.

    You send a laser beam with power P₀ = 5W into a cavity with inner reflectivity R = 0.99.
    It is irrelevant if the beam is diffused, when the light hits the inner
    walls of the cavity, it is reflected and the reflected power is P₀*R.
    The reflected light will then hit the opposite wall and be reflected
    again. The reflected power is now P₀*R*R.
    When the light has been reflected n times, the reflected power is
    P = P₀⋅Rⁿ.

    If n = 24170 the reflected power is P = 1.590e-105 W ≈ 0 W

    If the cavity is spherical with volume 1000 cm³, the diameter
    is D = 12.4 cm. Which means that the light will be reflected
    24170 times during 10 μs.
    If you integrate the energy of the laser light in the cavity
    it will be constant 2.05e-7 J
    During the 10 μs 5⋅1e-6 J is put into the cavity, so 4.9795e-05 J
    will be heat in cavity walls.

    The heat energy in the cavity walls will genearally be:
    E = (5⋅t - 2.05e-7) J where t is the time in seconds.

    The temperature of the walls will increase, and steady
    state will be when the outside of the cavity has a temperature
    so that the radiated power (and convection loss) is 5 W.

    At that time, the cavity will be filled by black body radiation
    with temperature equal to the inner walls.

    Have I missed something?

    --
    Paul

    https://paulba.no/

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  • From Thomas Heger@21:1/5 to All on Thu Nov 21 07:43:16 2024
    Am Mittwoch000020, 20.11.2024 um 16:57 schrieb ProkaryoticCaspaseHomolog:
    On Wed, 20 Nov 2024 14:46:05 +0000, rhertz wrote:

    As I wrote before, the cavity NEVER reaches a steady state (thermal
    equilibrium is just one possible goal to reach a steady state).

    The stored energy increases constantly until the temperature of the
    cavity
    walls (not cancelled by any means) destroy the material that form the
    cavity (either coatings or places on the cavity surface, making holes).

    No, because the temperature of the foil rises until the power emitted
    equals 5 watts. Once that happens, no further increase of stored
    energy occurs.

    P = ε * σ * T^4

    Let us assume a 10x10x10 cm cube with surface area 0.06 m^3
    So 5 watts total power emitted means 83 watts/m^2
    Assume ε = 0.13

    Let T_i be 273 K

    83 = ε * σ * (T_f^4 - T_i^4)
    11,260,344,593 = (T_f^4 - 5,554,571,841)
    T_f = 274.8 K

    In other words, the temperature of the foil rises to 1.8 degrees
    above room temperature.

    In physics, a steady state is a condition in which a system or process
    does not change over time, or any changes are balanced out. This means
    that the variables that define the system's behavior remain constant.
    Some examples of steady states include:

    Nature does not have 'closed systems'.

    What we call a system, that is actually our decision.

    Therefore the notation of 'elementary systems' (e.g. particles) is wrong.

    We decide, what we regard as a closed system, even if such things do not
    exist.

    Therefore we distinguish between a particle and its surrounding space
    and perceive the particles, as if it would be a thing (a closed system).

    But, in fact, e.g. an electron isn't particularly closed, because a
    pointlike thing ('the electron itself') is surrounded by its field.
    Now we have a contradiction between 'closed' and 'surrounding field'.

    But this contradiction occurs with other systems, too.


    Now 'steady state' and 'closed system' are seemingly interchangeable,
    hence a system is an entity, which lasts at least for some time, for
    which 'the defining variables' are constant.

    ...


    TH

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  • From Paul B. Andersen@21:1/5 to All on Thu Nov 21 22:33:35 2024
    Den 20.11.2024 02:02, skrev rhertz:

    Not bad for my estimation (2 gr) for the weight of the cavity,
    with inner surface of 7,850 mm², and thickness of 0.1 mm.


    If the cavity is spherical, the diameter will be D = 5 cm.
    The time light will use to go from one surface to the opposite
    surface is Δt = 16.33 ns

    Even if the cavity may have another shape, I will use
    Δt = 16.33 ns as the average time between the reflections
    of the laser beam.



    Den 20.11.2024 05:37, skrev rhertz:
    THE SYSTEM WILL NEVER REACH INTERNAL EQUILIBRIUM!

    That is IMPOSSIBLE because I'd be pumping ENERGY non-stop, forever if necessary. Can you get this, please?

    THERE IS NO AMPLIFICATION OF LASER POWER, AND NEVER WAS MEANT TO HAPPEN.

    WHAT HAPPEN IS A CONTINUOUS FEED OF ENERGY!. If you CAN'T SEE IT, then substitute the 5W laser by a hose POURING WATER INSIDE THE CAVITY. Some
    water falls out, but most remain UNTIL THE CAVITY IS FULL OF IT.

    When will it happen with the water analogy? Don't know/don't care.

    The only reason by which I used three days to fill the cavity up is
    because A LONGER PERIOD would accumulate much more perturbations and
    external interferences, complicating the statistical processing of the electrical signal that IS LINEARLY PROPORTIONAL to the accumulation of
    energy inside the cavity.

    If you REFUSE to understand this, I advise you to go back to college or
    high school, where you could re-learn elementary logic and arithmetic.

    Say no more.

    Power of laser P₀ = 5 W

    Let's look at some facts:

    Reflected power after n reflections
    P(n) = P₀⋅Rⁿ (1)
    where R is the reflectivity of the inner walls.

    The energy stored in the cavity as laser light:

    E = ∑{i = 1 to ∞}P₀⋅ Rⁱ⋅Δt = P₀⋅Δt ⋅∑{i = 1 to ∞} Rⁱ

    ∑{i = 1 to ∞} Rⁱ = R/(1-R) , a converging geometric array

    E = P₀⋅Δt ⋅R/(1-R) (2)

    Note that this is a constant.

    Calculations with R = 0.99:
    -------------------------

    Let us consider that all the laser light is absorbed
    when P(i) < 1e-10 W.
    From (1) we find: P(2455) = 9.62e-11
    t = 2455⋅Δt = 409 ns

    This means that 409 ns after the laser light enters the cavity,
    it will be absorbed by the wall.

    The energy stored as laser light in the cavity will according to (2) be:

    P₀⋅Δt ⋅R/(1-R) = 8.248e-8 J

    Was it this energy you thought would increase indefinitely?
    It won't. It is constant. And tiny.

    Calculations with R = 0.999998:
    -------------------------------

    From (1) we find: P(12350000) = 9.37e-11
    t = 12350000⋅Δt = 2.07 ms

    This means that 2.07 ms after the laser light enters the cavity
    it will be absorbed by the wall.

    The energy stored as laser light in the cavity will according to (2) be:

    P₀⋅Δt ⋅R/(1-R) = 4.166e-4 J



    Generally we can say that the laser light will be absorbed
    almost immediately after it enters the cavity, and the stored
    energy in the form of laser light will be tiny and constant.

    So all the 5 J that enters the cavity every second will heat
    the inner wall of the cavity. Since the walls are only 0.1 mm
    thick, the outer surface of the cavity will be approximately
    the same temperature as the inner surface, so after a short time
    the outer wall will radiate 5 W and the system will be in steady state.

    You could equally well have heated the cavity with a Bunsen burner.
    Do you think the mass increase due to the heat energy in the cavity
    would be measurable? :-D

    --
    Paul

    https://paulba.no/

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  • From Paul B. Andersen@21:1/5 to All on Fri Nov 22 21:30:39 2024
    Den 22.11.2024 00:22, skrev rhertz:
    On Thu, 21 Nov 2024 21:33:35 +0000, Paul B. Andersen wrote:

    Den 20.11.2024 02:02, skrev rhertz:

    Not bad for my estimation (2 gr) for the weight of the cavity,
    with inner surface of 7,850 mm², and thickness of 0.1 mm.

    Surface area 7,850 mm² !



    If the cavity is spherical, the diameter will be D = 5 cm.>> The time light will use to go from one surface to the opposite
    surface is Δt = 16.33 ns

    Even if the cavity may have another shape, I will use
    Δt = 16.33 ns as the average time between the reflections
    of the laser beam.

    Δt = D/c = 1.666e-10 s
    This is the value used in all the calculations.

    Δt = 16.33 ns is a typo never used in the calculations.





    Den 20.11.2024 05:37, skrev rhertz:
    THE SYSTEM WILL NEVER REACH INTERNAL EQUILIBRIUM!

    That is IMPOSSIBLE because I'd be pumping ENERGY non-stop, forever if
    necessary. Can you get this, please?



    Power of laser P₀ = 5 W

    Let's look at some facts:

    Reflected power after n reflections
       P(n) = P₀⋅Rⁿ    (1)
    where R is the reflectivity of the inner walls.

    The  energy stored in the cavity as laser light:

    E = ∑{i = 1 to ∞}P₀⋅ Rⁱ⋅Δt = P₀⋅Δt ⋅∑{i = 1 to ∞} Rⁱ

    ∑{i = 1 to ∞} Rⁱ  = R/(1-R) , a converging geometric array

    E = P₀⋅Δt ⋅R/(1-R)   (2)

    Note that this is a constant.

    Calculations with R = 0.99:
    -------------------------

    Let us consider that all the laser light is absorbed
    when P(i) < 1e-10 W.
     From (1) we find: P(2455) = 9.62e-11
    t = 2455⋅Δt = 409 ns

    This means that 409 ns after the laser light enters the cavity,
    it will be absorbed by the wall.

    The energy stored as laser light in the cavity will according to (2) be:

      P₀⋅Δt ⋅R/(1-R) = 8.248e-8 J

    Was it this energy you thought would increase indefinitely?
    It won't. It is constant. And tiny.

    Calculations with R = 0.999998:
    -------------------------------

     From (1) we find: P(12350000) = 9.37e-11
    t = 12350000⋅Δt = 2.07 ms

    This means that 2.07 ms after the laser light enters the cavity
    it will be absorbed by the wall.

    The energy stored as laser light in the cavity will according to (2) be:

      P₀⋅Δt ⋅R/(1-R) = 4.166e-4 J



    Generally we can say that the laser light will be absorbed
    almost immediately after it enters the cavity, and the stored
    energy in the form of laser light will be tiny and constant.

    So all the 5 J that enters the cavity every second will heat
    the inner wall of the cavity. Since the walls are only 0.1 mm
    thick, the outer surface of the cavity will be approximately
    the same temperature as the inner surface, so after a short time
    the outer wall will radiate 5 W and the system will be in steady state.

    You could equally well have heated the cavity with a Bunsen burner.
    Do you think the mass increase due to the heat energy in the cavity
    would be measurable? :-D



    Paul, as usual you fucked it up.

    No. All the calculations above are correct.


    CORRECTION 1:
    If the cavity is spherical, the diameter will be D = 10 cm (not 5 cm).
    NOTE 1: c= 3.0E+10 cm/s

    Surface area A = 7,850 mm² = 0.00785 m²
    r = √(A/4π) = 0.02499 m
    D = 2r ≈ 0.05 m

    The time light will use to go from one surface to the opposite
    surface is Δt = 0.333 ns (NOT 16.33 ns).

    c = 3e8 m/s
    Δt = D/c = 1.666e-10 s
    This is the value used in all the calculations above.


    NOTE 2: Δt = 0.333 ns IMPLY 3.00E+09 bounces/sec. With LIGO advanced technology, 1 photon per 5,000,000 photons is lost in every bounce.
    This represents a reflectivity R = 0.9999998.

    Above I wrote 12350000 bounces in 2.07 ms,
    equivalent to 5.966183574e9 bounces/sec.





    CORRECTION 2 (your fatal error:


    The  energy stored in the cavity as laser light:

    E = ∑{i = 1 to ∞}P₀⋅ Rⁱ⋅Δt = P₀⋅Δt ⋅∑{i = 1 to ∞} Rⁱ

    ∑{i = 1 to ∞} Rⁱ  = R/(1-R) , a converging geometric array

    E = P₀⋅Δt ⋅R/(1-R)   (2)

    Your error here is to use only the energy that exist in the first P₀⋅Δt interval. This represents ONLY 1.37E+39 photons (550 nm).

    I have done no error!


    You forgot that such quantity is supplied every 0.333 ns, being the
    amount of photons/sec 4.12E+48 (3 billions times bigger).

    Do you mean that the kinetic energy of the photons in
    the cavity is 3 billion times 4.166e-4 J ?

    There is a constant stream of photons with collective power 5 W
    into the cavity.

    At some time, say at t₁, there is one stream of photons bouncing
    between the walls in the cavity.
    Let's say the total number of photons in the stream is n, and
    the collective energy in the photons is 4.166e-4 J as calculated
    above.

    Some seconds later, say at t₂, there is one stream of photons
    bouncing between the walls in the cavity.
    The number of bouncing photons is still n, and their collective
    energy is 4.166e-4 J.

    At t₂ all the n photons that were under way at t₁ are now absorbed
    in the walls, and the energy of those photons is transformed to
    heat energy in the walls.

    At any time a few ms after the laser is switched on, there will
    be but n bouncing photons with the energy 4.166e-4 J in the cavity.

    So a few ms after the laser is switched on, the kinetic energy of
    of the photons from the laser will be constant 4.166e-4 J and
    the kinetic energy lost by the photons will be transformed to
    5 J heat energy in the walls every second.


    PER SECOND, you have to account the impact of reflectivity on 3 billion chunks of 1.37E+39 photons EACH, and make the calculations for losses cumulative with each bounce + new feed of P₀⋅Δt photons.

    The above means that you should count losses/sec IN THIS WAY:


    Loss 1 = ∑{i = 1 to 3,000,000,000} Rⁱ, for the first pack of photons.

    Loss 2 = ∑{i = 1 to 2,999,999,999} Rⁱ, for the 2nd. pack of photons.

    Loss 3 = ∑{i = 1 to 2,999,999,998} Rⁱ, for the 3rd. pack of photons. .....

    Loss n = ∑{i = 1 to 3,000,000,001-n} Rⁱ, for the nth. pack of photons.

    THEN CALCULATE THE SUM OF LOSSES FOR THE 3 BILLIONS PACKS OF PHOTONS.

    As explained above, it is very simple:
    The kinetic energy lost by the photons from the laser will
    be transformed to 5 J heat energy in the walls every second.

    And, as I said above but you didn't read:

    Generally we can say that the laser light will be absorbed
    almost immediately after it enters the cavity, and the stored
    energy in the form of laser light will be tiny and constant.

    So all the 5 J that enters the cavity every second will heat
    the inner wall of the cavity. Since the walls are only 0.1 mm
    thick, the outer surface of the cavity will be approximately
    the same temperature as the inner surface, so after a short time
    the outer wall will radiate 5 W and the system will be in steady state.

    You could equally well have heated the cavity with a Bunsen burner.
    Do you think the mass increase due to the heat energy in the cavity
    would be measurable? 😂


    You'll understand that such is not an easy task, in particular when calculating the losses per hour on in 72 hours.

    The kinetic energy lost by the photons is 5 J per second
    and (18000 - 4.166e-4) J after 72 hours.

    The system will obviously be in steady state a long time
    before 72 hours.
    To find the temperature of the cavity you must find what
    temperature the cavity has to have to radiate (and loose
    by convection) 5 W.
    You must obviously take into account that the cavity will
    receive a black body radiation with temperature equal
    to the temperature of the walls pm your room.


    YOUR NUMBERS ARE WAY OFF!! (3,000,000,000 off maybe?).

    Do you claim the loss after 72 hours is 3,000,000,000 times 18000 J ?

    Bottom line:
    It doesn't matter how you put energy into a closed cavity.
    In the cavity there will be a black body radiation with
    temperature equal to the temperature of the walls.

    The reflectivity, albedo or colour of the inner surface
    of the cavity are irrelevant. The radiation in the cavity
    will always be black body radiation.

    Make a hole in your cavity, and you have a perfect
    black body radiation source.

    Its temperature will not be very high, though-


    Now smile, asshole.

    :-D

    --
    Paul

    https://paulba.no/

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  • From Paul B. Andersen@21:1/5 to All on Sat Nov 23 19:29:49 2024
    Den 22.11.2024 22:03, skrev rhertz:
    On Fri, 22 Nov 2024 20:30:39 +0000, Paul B. Andersen wrote:

    <snip all the history of your life. You didn't read my disclaimer>

    Sorry about that.

    I see now that you posted the disclaimer 17.31 GMT+1,
    which is long before I posted the response 21.30 GMT+1.
    Your post I responded to was posted 00.22 GMT+1.
    I began writing my response in the morning, but was
    otherwise occupied during the day, and completed
    the response in the evening without reading the posts
    that were posted in the meantime.

    If I had read your disclaimer before I wrote
    my response, I would have known that you agree
    that the experiment is impossible, and I wouldn't
    have written it.



    Bottom line:
    It doesn't matter how you put energy into a closed cavity.
    In the cavity there will be a black body radiation with
    temperature equal to the temperature of the walls.

    The reflectivity, albedo or colour of the inner surface
    of the cavity are irrelevant. The radiation in the cavity
    will always be black body radiation.

    Make a hole in your cavity, and you have a perfect
    black body radiation source.

    Its temperature will not be very high, though-



    It is not a BB radiation source!

    I see that ProkaryoticCaspaseHomolog has given the obvious
    response to your statement.
    "A closed cavity at equilibrium above absolute zero will contain
    black body radiation, regardless of the composition of its walls."

    Compare that to my statement quoted above.


    You ignored the fact that the heat goes away from the cavity. It doesn't remain neither inside nor outside. It's eliminated by cooling
    mechanisms, as I wrote as an initial condition. Read all the posts.

    I did not ignore that.

    Den 21.11.2024 22:33, skrev Paul B. Andersen:
    "So all the 5 J that enters the cavity every second will heat
    the inner wall of the cavity. Since the walls are only 0.1 mm
    thick, the outer surface of the cavity will be approximately
    the same temperature as the inner surface, so after a short time
    the outer wall will radiate 5 W and the system will be in steady
    state."

    Even with cooling, the temperature of the outer surface of
    the cavity will be higher than the ambient temperature.


    There is no light energy left within the cavity, nor heat energy outside
    it. You better think again about it.

    Even if the temperature of the inner surface is as low as 20⁰C
    there will be black body radiation with temperature 293.15⁰K.
    The spectrum of this BB radiation will peak at λ ≈ 10m
    so most of the radiation will be in hf and vhf range.


    You also ignored my post apologizing to all people that participated in
    this thread. That makes you a bigger ASSHOLE than what I thought.

    Now, start thinking in my NEXT IDEA:

    Willing to try to prove/disprove E=mc² at a macroscopic level, I'll
    think of an experiment that incorporates electromagnetic oscillations
    passing through the cavity, which will be converted in a CAPACITOR, by cutting it in halves and isolating them with a thin ring.

    What I propose to MEASURE is the changes in the frequency of the LC oscillator, within a time window of about 3 msec, which repeats
    permanently.

    I'll use a relationship between mass and capacitance for the cavity,
    with frequency around 1 Mhz or greater.


    It was a failed idea for an experiment, but there are OTHER WAYS to
    check E=mc² at a macroscopic level, without resorting to nuclear energy
    crap (Kg evaporated vs. energy provided), or else.

    Ask ChatGPT:


    any other non-relativistic means to prove E=mc^2?
    or
    Is there any way to prove E=mc^2 at higher level than quantum?
    or
    can I use electrostatic energy?


    The last one gave interesting insights. Ask to it sequentially the above lines.



    Keep smiling, asshole.

    :-D

    --
    Paul

    https://paulba.no/

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  • From Paul B. Andersen@21:1/5 to All on Tue Nov 26 21:26:18 2024
    Den 25.11.2024 22:54, skrev rhertz:
    Prokaryotic, I was thinking about what you wrote on the cavity behaving
    as a black body and, as I wrote before, I completely disagree to take it
    as a black body radiating energy, once equilibrium has been reached.

    It will be black body radiation _within_ the cavity.

    To repeat what Prokaryotic and I have said before:
    (Prokaryotic's wording which is better than mine)

    "A closed cavity at equilibrium above absolute zero will contain
    black body radiation, regardless of the composition of its walls."

    I find it strange that you don't know this.
    But it is a fact. Let's see why:

    I think you will agree that if the inner walls are completely
    black, that is the absorptance and emissivity ε = 1, then we will
    have blackbody radiation within the cavity.
    The inner walls will radiate a power which will be completely
    absorbed when it hits the opposing wall.
    P = σAT⁴ where σ is a constant, A is the area of the inner walls
    and T is the absolute temperature of the wall.

    However, the emissivity ε isn't 1, it is less than one.
    The wall will radiate the power P = ε⋅σAT⁴.
    Since the reflectivity R = 1-ε, the opposing wall will not
    absorb the power completely, but will reflect some of it back
    to the the opposing wall which will reflect some of it back ...

    The radiated and reflected power from the wall will be:

    P = ε⋅σAT⁴ + ε⋅σAT⁴⋅R + ε⋅σAT⁴⋅R² + ε⋅σAT⁴⋅R³ + ...

    converging geometric series Note: ε = (1-R)

    P = ε⋅σAT⁴/(1-R) = σAT⁴

    So it will be black body radiation within the cavity
    even if ε < 1 and R > 0.

    You will never understand your experiment if
    you do not understand and accept this.


    My main doubt was that, once in equilibrium and having gained as heat
    all the energy supplied by the 5W laser, the aluminum cavity HAD TO
    radiate using the external surface AS WELL AS the internal surface. I
    thought that almost HALF of the heat was going to be radiated INTO THE CAVITY.

    This is a strange statement.
    In steady state the external surface of the cavity must obviously
    radiate (or loose by convection) 5 W.
    This is what determines the temperature of the outer surface of
    the cavity and thus the temperature T of the inner wall.

    See Prokaryotic's calculations.

    --
    Paul

    https://paulba.no/

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  • From Paul B. Andersen@21:1/5 to All on Thu Nov 28 22:45:35 2024
    Den 28.11.2024 22:39, skrev Paul B. Andersen:
    So the stored radiation energy within the cavity would be:

    E = 4⋅σ⋅V⋅T_f⁴ = 1.15e-08 Joules

    Typo:

    E = 4⋅σ⋅V⋅T_f⁴/c = 1.15e-08 Joules


    Quite far from the 477.5 Joules you fantasised  about.

    In fact, the heat energy stored in the aluminium would be much higher,
     E = 0.06 Joules. (If my calculation is correct.)

    Not much to weight, is it? :-D



    --
    Paul

    https://paulba.no/

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  • From Paul B. Andersen@21:1/5 to All on Thu Nov 28 22:39:47 2024
    Den 28.11.2024 01:09, skrev rhertz:



    I'm going to tell this one more time, because it's the center of the
    problem:


    Using a modified Stefan's formula (by 4/c) to calculate the internal temperature of a small aluminum cavity IS AN ABERRATION OF COMMON SENSE.

    I see ProkaryoticCaspaseHomolog has explained you what the equation
    u = 4σT^4/c means.

    Nice guy as he is, he hasn't explained why your statement below
    is idiotic.

    But you know me, I like to rub it in.


    In your calculation of 1,000,000+ K inside the cavity, YOU SHOULD HAVE STOPPED at 660.3"C (930.3 K) when ALUMINUM MELTS.

    Why did you persist in using such stupid value? I can't figure it out.

    I can figure it out:

    |On Mon, 25 Nov 2024 21:54:34 +0000, rhertz wrote:
    This means that half of the accumulated 955 Joules remain within the
    cavity.

    So YOU claimed the stored energy within the cavity is 477.5 Joules.

    According to ProkaryoticCaspaseHomolog (with small error corrected):

    If that had been true, the stored energy would be E = 9.12e5 J/m³ so
    E = 4⋅σ⋅T⁴/c where σ = 5.67e-8 and T = √(√(E⋅c/4σ)) = 186365⁰K

    So YOUR 477.5 Joules is a crazy value.

    A more realistic temperature when we know that the cavity
    must get rid of 5W is:

    |Den 26.11.2024 03:25, skrev ProkaryoticCaspaseHomolog:
    Assuming that the environmental temperature is 293 K and that the
    experiment is conducted in vacuum,

    P = ε σ A_e (T_f^4 - T_i^4)
    5 = 0.13 * 5.67e-8 * 0.03144 * (T_f^4 - 293^4)
    5 = 0.13 * 5.67e-8 * 0.03144 * (T_f^4 - 7,370,050,801)
    21,575,509,276 = T_f^4 - 7,370,050,801
    T_f^4 = 28,945,560,077
    T_f = 412.5 K (actually, the numbers only justify 1-2 sig figures)

    With 1 mm thick wall, the temperature difference between
    the inner wall and the outer wall would be ΔT = 0.0008⁰K which
    is negligible in this context.

    So the stored radiation energy within the cavity would be:

    E = 4⋅σ⋅V⋅T_f⁴ = 1.15e-08 Joules

    Quite far from the 477.5 Joules you fantasised about.

    In fact, the heat energy stored in the aluminium would be much higher,
    E = 0.06 Joules. (If my calculation is correct.)

    Not much to weight, is it? :-D

    --
    Paul

    https://paulba.no/

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  • From Paul B. Andersen@21:1/5 to All on Fri Nov 29 13:54:58 2024
    Den 28.11.2024 22:39, skrev Paul B. Andersen:


    The spherical cavity:
    radius r = 0.05 m
    area A = 0.03142 m²
    volume V = 5.236e-4 m³
    wall thickness d = 0.001 m

    A realistic temperature when we know that the cavity
    must get rid of 5W is:

    |Den 26.11.2024 03:25, skrev ProkaryoticCaspaseHomolog:
    Assuming that the environmental temperature is 293 K and that the experiment is conducted in vacuum,

    P = ε σ A_e (T_f^4 - T_i^4)

    Emissivity ε = 0.13, reflectivity R = (1-ε) = 0.87,
    Constant σ = 5.67e-8 W/m²⋅⁰K⁴
    Laser power P = 5W
    Ambient temperature Ti = 293 ⁰K

    The temperature T_f of the outer surface of the cavity is:

    T_f = √(√((P+ε⋅σ⋅Aₑ⋅Tᵢ⁴)/ε⋅σ⋅Aₑ)) = 412.5 ⁰K


    With 1 mm thick wall, the temperature difference between
    the inner wall and the outer wall would be  ΔT = 0.0008⁰K which
    is negligible in this context.

    The temperature on the inner surface can be considered
    equal to the temperature of the outer surface.


    So the stored radiation energy within the cavity would be:

    E = 4⋅σ⋅V⋅T_f⁴/c = 1.15e-08 Joules

    This is the total energy in the BB radiation.
    But the BB radiation energy supplied by the laser is:

    Eᵣ = 4⋅σ⋅V⋅(T_f⁴ - Tᵢ⁴)/c = 8.5435e-09 Joule

    The energy stored in the cavity as laser light is:

    Eₗ = P⋅2r/c + R⋅P⋅2r/c + R²⋅P⋅2r/c + R³⋅P⋅2r/c + . . .
    Eₗ = (P⋅2r/c)/(1-R) = (P⋅2r/c)/ε = 1.282e-08 Joule

    Note that the energy stored as laser light is slightly
    higher, but of the same order of magnitude as the energy
    stored as black body radiation.


    In fact, the heat energy stored in the aluminium would be much higher,

    Density of aluminium D = 2700 kg/m³
    Specific heat capacity s = 0.88 J/g⁰K

    The mass of the aluminium cavity is:
    m = D⋅A⋅d = 0.0848 kg = 84.8 g

    ΔT = T_f - Tᵢ = (412.5 - 293)⁰K = 119.5 ⁰K

    The energy stored as heat:
    Eₕ = m⋅s⋅ΔT = 8.92 Joule

    The energy stored as radiation is less than the uncertainty in Eₕ
    and can be ignored.

    The mass equivalence of Eₕ is Δm = Eₕ/c² = 9.91e-17 kg

    Hardly measurable! :-(

    --
    Paul

    https://paulba.no/

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  • From Paul B. Andersen@21:1/5 to for why I "fucked it up big time" w on Sat Nov 30 14:37:51 2024
    Den 29.11.2024 03:58, skrev rhertz:


    You have barely written an OP in the last 5 years, and when you did, you fucked it up big time.

    I suppose this is the paper we "discussed":
    "What GR predicts for the perihelion advance of planets" https://paulba.no/pdf/GRPerihelionAdvance.pdf

    Can you please explain how I "fucked it up big time"?
    Do you find anything wrong in it?

    Ashamed of those who mocked you, you went into
    the "silence cone" for months.
    But you were reading every single post,
    looking for what? Consolation? A friendly hand to rescue you from exile?

    I did that for you, remember? I LIED to save your ass(face), and you
    thank me.

    Oh, that's right.
    In the post quoted below, you did indeed "Save my ass."
    See explanation of how you did it below the quoted post of mine.


    Subject: Re: What GR predicts for the perihelion advance of planets
    |Paul B. Andersen   Nov 21, 2021, wrote:
    |
    Den 21.11.2021 08:23, skrev Richard Hertz:

    The formula (8) on the paper is equal to Einstein's Eq. 13 (paper
    Nov. 18, 1915)

    https://tinyurl.com/yzzbratp


    (Equation 13) ε = + 3π α/[a (1 – e²)]

    with an error lower than 1.6E-07


    Or equation (14): ε = 24π³a²/T²c²(1−e²)

    This is the equation you will find in many books and papers.

    T² = 4π²a²/GM (1)
    where T is the period of a test particle in orbit
    around a mass M. a is the semi-major axis.

    My equation (8): ε = 6π(GM)²/G(M+m)a(1−e²)c²

    If we in this equation set (GM)²/G(M+m) ≈ GM when m/M << 1
    and from (1): GM = 4π²a²/T²
    we get the equation: ε ≈ 24π³a²/T²c²(1−e²)
    which is the same as Einstein's equation (14)

    The difference is that Einstein's equation (the equation commonly used)
    is the perihelion advance of a test particle in orbit around a mass M,
    while my equation (8) is the perihelion advance of a mass m in orbit
    around a mass M.

    The relative difference is (as you said):
    ((GM)²/G(M+m) - GM)/GM = -1.66E-7
    which obviously is negligible, probably less than the precision
    of G, M and m.

    That's why Einstein's equation (14) safely can be used.


    BTW, thanks for a sensible post.
    You haven't produced many of those lately.

    --
    Paul



    I LIED because I took pity of your "exile", so I wrote that your
    calculations were correct, within an error margin.

    Right.
    I was so ashamed of having written: https://paulba.no/pdf/GRPerihelionAdvance.pdf
    that I went into the "silence cone" for months.

    But when you saved my ass by writing:
    "(Equation 13) ε = + 3π α/[a (1 – e²)]
    with an error lower than 1.6E-07"

    I could start posting again.

    Sounds reasonable, doesn't it? :-D


    ---------------------------

    Below I will leave your lethal and rational arguments
    for why I "fucked it up big time" when I wrote: https://paulba.no/pdf/GRPerihelionAdvance.pdf


    After that, you started to writing posts again, but NEVER tried again to write an OP (Original Post). You should keep this in mind.

    Instead, you choose to continue with your usual M.O., which is to read everything and insert comments, but not an OP again.


    My behavior is exactly THE OPPOSITE ONE: I mostly write OP, even with
    the most ridiculous idea that I come up with, BECAUSE I'm here to have
    fun. FUN, not scientific research.

    To do that, I think about different ideas (as a hobby), and if I find something that can stir the waters, creating controversy to animate this circus, I wrote the OP with my best criteria and my best thoughts.


    I pretend to animate the circus, not to gain a Nobel Prize. And, of the
    most importance, I INVENT most of the content (original thinker), taking
    care to make the most of sense and the lowest amount of ridiculous
    equations and assessments. To do so, I first think, then I do some
    research to validate the ideas. Even if I can't find any support, but
    I'm convinced the idea is good, I create the OP and wait for the hell
    broke loose.

    Your behavior is mostly parasitic, as you live from the ideas of others.

    You live citing and quoting papers from others that support relativity.
    This behavior of you, playing safe from your comfort zone shows, among
    other things, that you are an intellectual coward. You are afraid that
    you might publish something wrong or stupid.

    I don't care about what others think about me, but you CAN DIE if you
    fuck it up, which you did many times in the last decade and a half.

    I also learn by successive refinements of the ideas in the OP, through interactions with others. And if I make a mistake, and I realize it, I APOLOGIZE without any shame.


    Now, think about what I wrote, and keep smiling, asshole.

    Good to see that you are your normal, agreeable self.


    PS
    Don't forget to explain why I "fucked it up big time" when I wrote this: https://paulba.no/pdf/GRPerihelionAdvance.pdf

    I missed it in 2021.

    --
    Paul

    https://paulba.no/

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  • From Tom Roberts@21:1/5 to ProkaryoticCaspaseHomolog on Wed Dec 11 15:06:04 2024
    On 11/23/24 1:12 AM, ProkaryoticCaspaseHomolog wrote:
    [...] Of all the schemes I could think of whereby a DIY amateur scientist
    can verify E=mc², the only feasible one that I can think of is to
    measure the energy of electron-positron annihilation.

    You'll need a budget of at least $10,000.00 (probably more), and I doubt
    you could obtain a useful resolution (say, 1%).

    I'd need
    the help of an expert former EE to put things together (hint, hint).

    Or better, the assistance of an experimental particle physicist. But it
    would be quite difficult to interest someone with the requisite
    skills.... I have those skills, but am not interested.

    Sealed sodium-22 positron sources are readily available for sale
    online.

    Yes. But I don't know if they will sell to an unaffiliated DIY
    experimenter. Sales of radioactive objects are often restricted, and
    they are usually prohibited in standard delivery channels (UPS, FedEx,
    USPS, ...).

    Calibrating the gamma-ray detectors will be the hard part.

    Yes. You'll need several different gamma sources with known emission
    energies.

    Once
    calibrated, I'd place two gamma-ray detectors 180 degrees apart
    equidistant from an appropriate target. Connected to the detectors
    will be a whole slew of equipment for coincidence counting, energy measurement, etc. that the expert former EE will be responsible for.

    With luck, the DIY experimenter will be able to confirm the
    simultaneous emission of two 511 keV photons from each annililation.

    This is certainly doable. Whether it is worthwhile is a quite different
    issue -- personally I doubt it.

    Note: this is the sort of experiment that could be in the syllabus of
    the appropriate undergraduate lab class at a good college or university.
    (They would use the equipment for several different experiments and many students.)

    Tom Roberts

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