Expert: Philip Stahl - 2/27/2004

Question
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Followup To
Question -

I guess that your did answer the question I asked but   That is not what I wanted to ask.

I'll try again

I've been trying hard not to sound like some sort of nut.  As the say ""A little knowledge can be a dangerous thing  " or make you ask stupid questions ""

I have read about the quest of things that might be travling faster than the speed of light (c).

Since we know that by the time a photron gets from the sun to earth, The earth has rotated for another 8.33 minutes

So.... if were to detect any events that we could attribbute to the sun before visable sunrise or 8.33 minutes ahead of the visable sun they would have to travel faster than light(c).

Hummmmm   May still sound like a nut.

Gerry McDaniel
mcdaniel@iglou.com
     
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Followup To

Either I missed part of your answer to my question  or  I was not clear enough with the questuon.

I'll try again.

At tme time we see the suns disk appear at the horizion..  the earth has roated for some 9 min since the photons left the sun.

Therefore when we see the sunrise the sun (star) is actually 9 min higher above the horizipn.

If there is any detectable events associated with actual sun (star)Before appearnce above the horizion  or 9 min higher than the visable sunrise ... those events must have traveled faster than the photons leavind the sun.

Gerry McDaniel
mcdaniel@iglou.com


Question -
I have read that it takes light from the sun about 9 min to reach earth.  If so ... that means that the physical sun is a bit above the horizion by the time we see the sunrise.

Are there test to tell the real location of the sun above the horizion?

Gerry McDaniel
mcdaniel@iglou.com
Answer -
Follow-up:

The next to last paragraph should read:


"By the same token, at *visible sunrise*, the position of the visible Sun will appear *later* on the observer's horizon, than its theoretical counterpart. (Or if you prefer, the theoretical Sun is closer to the observer's zenith, higher in altitude, than a simple observation would suggest)."

In both cases (sunrise, sunset), the effect of refraction is to increase the length of day, or the interval of time the Sun is above the horizon - over what it would be theoretically.
Answer -
Hello.

I suspect the first part of my answer wasn't provided, so will give that again.

If this still doesn't answer your question, please feel free to use a follow-up.

Determination of astronomical twilight, of sunrise, or sunset, doesn't
really take into account the 'time lag' introduced by virtue of the Sun's
distance from Earth. (About 150 million kilometers, translated to 500
seconds, given c = 300,000 km/s).

We're only concerned with the real time 'received' Sun or solar image, and
where that is in relation to the horizon.

What one does know is that the real, physical Sun, would have *already*
gone below the horizon, by the time we see the image Sun setting. (Since
we are receiving the light-image 500 seconds or 8.33 minutes *later*).

Conversely, it would already be well *above* the visible Sun at sunrise.
By an amount of angle we can obtain from the time differential of 8.33
mins.

Since we know the Earth rotates through 15 degrees in 1 hour, then it
turns through 1 degree every 4 mins. (60' per degree). For an eight
minute, 30 second+  span, this would be just over 2 and 1/2 degrees.

Of far more concern to astronomers, actually astrometrists (concerned with
position of celestial objects) is the effect of atmospheric *refraction*
on the image we do see, at sunrise or sunset.

The numerical value of this refraction, or 'horizontal refraction' amounts
to some 34' or just over half a degree of arc. Its effect is to make the
body - in this case the Sun- appear nearer to the zenith (overhead point)
than it otherwise would be. Or, more simply, higher above the horizon than
if there were no atmosphere.

It follows from this that when we observe the Sun setting, the true zenith
distance is (90 degrees +  34'), i.e. the visible Sun is already 34' below
the horizon. What we are actually getting is the refracted image.

Hence, the time of *visible sunset* (based on the refracted image) will
always be later than theoretical sunset (if there were no atmosphere) by
the time equivalent to 34'.

(rest of answer already given as follow-up)

Answer
Hello again.

You asked:

"I have read about the quest of things that might be travling faster than the speed of light (c).

Since we know that by the time a photron gets from the sun to earth, The earth has rotated for another 8.33 minutes

So.... if were to detect any events that we could attribbute to the sun before visable sunrise or 8.33 minutes ahead of the visable sun they would
have to travel faster than light(c)."

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Your points, questions are interesting, but for astronomers kind of like arguing "how many angels can dance on the head of a pin". They really don't command a lot of interest, or desire for inquiry.

First, there is absolutely no firm evidence, never mind the speculations, that anything can travel faster than light.

Tachyons have often been mentioned in various forums, but no one has yet detected a tachyon. It remains an intriguing proposed mathematical entity, but with no basis in observed fact.

Similarly, in a paper appearing in the journal Nature, in July 2000, physicists at the NEC Research Institute in Princeton, New Jersey claimed to have broken the limit set by the speed of light. They achieved this by firing a laser pulse into a glass chamber filled with a cesium (Cs) atom vapor.

NEC's Lijun Wang, in fact, insisted he'd created an experiment in which light speed was not merely exceeded by an added increment, but by a factor of three hundred! (300c)  This meant that an almost identical light pulse exited the chamber and traveled about sixty feet before the main part of the laser pulse finished entering the chamber, Wang said.

Needless to say, this flouts well-known accepted precepts of causality. (Wherein causes are assumed to precede effects). ). Relativity purists, however, have been gratified to know that a number of physicists question the interpretation of the results.

As in the case of tachyons, validity will therefore have to await a confirmation of the experimental results.

Given these examples, and the fact that Einstein's relativity limits on the speed of light remain intact, astronomers and physicists see no point in pursuing whether any events on the Sun - under certain conditions of detection- represent FTL events.

What we want to see *first* is the lab or other validations, which would then incline us to examine FTL phenomena in nature, and take them seriously.

No, your question is not "nutty" at all, since speculation is the life blood of imagination, as well as scientific and empirical pursuit. It's just that the science-physics community won't be prompted to explore such issues or possibilities, until more fundamental thresholds are met. That includes stong confirmations for any and all FTL claims. In particular, for the "objects" and/or experiments claimed to represent FTL manifestations.