"Schoenfeld" wrote in message
ups.com...

We fill a box with a radioactive material which randomly emits
radiation. The box has a shutter, which is opened and immediately
thereafter shut by a clock at a precise time, thereby allowing some
radiation to escape. So the time is already known with precision. We
still want to measure the conjugate variable energy precisely. We
measure the energy by weighing the box before and after. The
equivalence between mass and energy from special relativity will allow
us to
determine precisely how much energy was left in the box.

The experiment allows us to determine the exact energy of the box at
the exact time, violating quantum uncertainty with extreme prejudice.
:-)

Trick questions and physics don't mix.

Schoenfeld has made two measurements of the box's weight.
One from t = - infinity to t = 0. The other, from t = delta_t
to t = + infinity, where delta_t is the time interval over which
the shutter is open. By HUP, each weight determination, W1,
and, W2, is precise. delta_t can also be known precisely.

Where's the HUP violation ? The measurements of W1, W2,
and delta_t were performed over orthogonal time intervals.

Now repeat the experiment: is

delta_W = W1 - W2 = constant ?

[Old Man]

Old Man wrote:
Schoenfeld has made two measurements of the box's weight.
One from t = - infinity to t = 0. The other, from t = delta_t
to t = + infinity, where delta_t is the time interval over which
the shutter is open. [...]

_IF_ he could do that, then his claims might be able to hold up. But he
cannot possibly make any measurement of infinite duration. The finite
duration of the measurement is related to its finite accuracy (but there
are also noise, etc. as I said before).

His basic fallacy is assuming infinite accuracy in his measurements. He
is essentially ignoring the HUP and its effects on his measurements, and
then claiming he has "proven" that the HUP isn't valid....


Tom Roberts

"Tom Roberts" wrote in message
...
Old Man wrote:
Schoenfeld has made two measurements of the box's weight.
One from t = - infinity to t = 0. The other, from t = delta_t
to t = + infinity, where delta_t is the time interval over which
the shutter is open. [...]

_IF_ he could do that, then his claims might be able to hold up. But he
cannot possibly make any measurement of infinite duration. The finite
duration of the measurement is related to its finite accuracy (but there
are also noise, etc. as I said before).

His basic fallacy is assuming infinite accuracy in his measurements. He is
essentially ignoring the HUP and its effects on his measurements, and then
claiming he has "proven" that the HUP isn't valid....

The trick part of Schoenfeld's question is that delta_t is
non sequitur. No matter the value of delta_t, total energy
is observed to be conserved.

The point here isn't over the separate measurability of delta_t
or of W1 or of W2. They're measured sequentially in
time. However, there's no guarantee that the determination
of W2 isn't effected by the measurements of W1 and delta_t.

Let delta_E be the measured release of radiation during time
interval, delta_t. Then, conservation of energy for each event:

delta_E = ( c^2 / g ) ( W1 - W2 )

Note the absence of delta_t in the above. However, over
many measurements,

Std_Dev{ delta_E } = hbar / 2 * delta_t .

Std_Dev{ W1 - W2 } = ( g / c^2 ) ( hbar / 2 * delta_t )

This is exactly how one determines the energy width and /
or the lifetime of a nuclear state. (W1, W2) from particle
kinematics and / or delta_E from gamma energy. For each
event, they add up via conservation of energy. No HUP.

Delta_t isn't involved in kinematics. Get delta_t via HUP.

[Old man]

Tom Roberts

Old Man wrote:
"Tom Roberts" wrote in message
...
Old Man wrote:
Schoenfeld has made two measurements of the box's weight.
One from t = - infinity to t = 0. The other, from t = delta_t
to t = + infinity, where delta_t is the time interval over which
the shutter is open. [...]

_IF_ he could do that, then his claims might be able to hold up. But he
cannot possibly make any measurement of infinite duration. The finite
duration of the measurement is related to its finite accuracy (but there
are also noise, etc. as I said before).

His basic fallacy is assuming infinite accuracy in his measurements. He is
essentially ignoring the HUP and its effects on his measurements, and then
claiming he has "proven" that the HUP isn't valid....

The trick part of Schoenfeld's question is that delta_t is
non sequitur. No matter the value of delta_t, total energy
is observed to be conserved.

The point here isn't over the separate measurability of delta_t
or of W1 or of W2. They're measured sequentially in
time. However, there's no guarantee that the determination
of W2 isn't effected by the measurements of W1 and delta_t.
-------------

W2 is not affected by measuring W1 - in case that
two photons in opposite direction were
*leaving* the W1

iow the moment they left W1 with no recoil
they have no more any connection to W1


Y.Porat
------------------