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Sound Pulses Exceed Speed of Light
Live Science ^ | January 12, 2007 | Charles Q. Choi

Posted on 09/02/2017 12:06:20 AM PDT by 2ndDivisionVet

A group of high school and college teachers and students has transmitted sound pulses faster than light travels—at least according to one understanding of the speed of light.

The results conform to Einstein's theory of relativity, so don't expect this research to lead to sound-propelled spaceships that fly faster than light. Still, the work could help spur research that boosts the speed of electrical and other signals higher than before.

The standard metric for the speed of light is that of light traveling in vacuum. This constant, known as c, is roughly 186,000 miles per second, or roughly one million times the speed of sound in air. According to Einstein's work, matter and signals cannot travel faster than c.

PVC science

However, physicist William Robertson at Middle Tennessee State University in Murfreesboro, along with a high school teacher, two college students and two high school students, managed to, depending on how you look at it, transmit sound pulses faster than c using little more than a plastic plumbing pipe and a computer's sound card.

"This experiment is truly basement science," Robertson told LiveScience.

The key to understanding their results, reported online Jan. 2 in the journal Applied Physics Letters, is envisioning every pulse of sound or light as a group of intermingled waves. This pulse rises and falls with energy over space, with a peak of strength in the middle.

Messing with Light Speed

In an unrelated previous experiment, Robert Boyd at the University of Rochester used similar principles to make pulses of light travel backward and faster than c.

Robertson and his colleagues transmitted sound pulses from the sound card through a loop made from PVC plumbing pipe and connectors from a hardware store. This loop split up and then recombined the tiny waves making up each pulse.

This led to a curious result. When looking at a pulse that entered and then exited the pipe, before the peak of the entering pulse even got into the pipe, the peak of the exiting pulse had already left the pipe.

If the velocities of each of the waves making up a sound pulse in this setup are taken together, the "group velocity" of the pulse exceeded c.

"I believe that this is the first experimental demonstration of sound going faster than light," Robertson said. Past research has proven it possible to transmit electrical and even light pulses with group velocities exceeding c.

Common thing?

Robertson explained this faster-than-light acoustic effect is likely commonplace but imperceptible.

"The loop filter that we used splits and then recombines sound along two unequal length paths," he said. "Such 'split-path' interference occurs frequently in the everyday world."

For example: "When a sound source is located near a hard wall, some sound reaches the listener directly from the source whereas some sound travels the longer path that bounces the sound off the wall. The sounds recombine at the listener," Robertson said. However, the weakness of the signals and the fact that any resultant differences in timing are very slight "mean that we would never be able to hear this effect."

None of the individual waves making up the sound pulses traveled faster than c. In other words, Einstein's theory of relativity was preserved. This means one could not, for instance, shout a message faster than light.

Still, this research might have engineering applications. Robertson explained that although it is not possible to send information faster than light, it seems these techniques could make it possible to route slower-than-light signals in electronic circuits faster than before.


TOPICS: Business/Economy; Science
KEYWORDS: 2007; einstein; physics; sound; tenyearsago
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To: 2ndDivisionVet

Depending on how you look at it, Barry Soeotoro was a great president.

Depending on how you look at it, Bill Clinton was a wonderful mentor to Monica Lewenski.

Depending on how you look at it, letting Mexicans overrun the country in a sign of love.

Depending on how you look at it, Houston just got a little rain.

Depending on how you look at it, physicist William Robertson at Middle Tennessee State University in Murfreesboro, along with a high school teacher, two college students and two high school students think we are all as dumb as a sack of hammers.


21 posted on 09/02/2017 5:52:26 AM PDT by Delta 21 (AntiFa and BLM should be on the United States list of Terrorist Organizations)
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To: 2ndDivisionVet

An observable response with science and scientific examples is that SOMEBODY knows this stuff! Like many others of us know about Pantone color charts, balancing fuel injectors, crocheting with long fiber cotton, or cutting valley cripple jacks freehand.

The specialized language is gobbledygook to the un-initiated, but plain-as-day to the practitioners.

The truly freaky part is that things like Relativity were theorized over 100 years ago, and one guy knew it.
Today, well-versed middle schoolers can give you the basics about it.

We do move forward, despite what some folks claim.

#MAGA
#Build The Wall


22 posted on 09/02/2017 6:10:52 AM PDT by Macoozie (Handcuffs and Orange Jumpsuits)
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To: 2ndDivisionVet

If you are no more than 187,000 miles from me as I type this, you are now, this instant, wondering where is that loud weird laugh coming from.


23 posted on 09/02/2017 6:30:20 AM PDT by Wuli
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To: 2ndDivisionVet

I find it doubtful that a professor from a lower to mid level college, a high school teacher and a few students were able to exceed the speed of light when no one else has.


24 posted on 09/02/2017 6:40:55 AM PDT by Brooklyn Attitude (Let's start putting signs on Confederate statues that read "DEMOCRAT".)
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To: 2ndDivisionVet

Well, that explains the “kawoosh” noise when Marty McFly’s DeLorean goes through time.


25 posted on 09/02/2017 7:43:34 AM PDT by pabianice (LINE)
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To: pabianice

It was NOT his car!


26 posted on 09/02/2017 8:19:47 AM PDT by I am Richard Brandon
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To: pabianice

It was NOT his car!


27 posted on 09/02/2017 8:19:48 AM PDT by I am Richard Brandon
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To: pabianice

Sorry! I seem to have met myself coming back.


28 posted on 09/02/2017 8:20:57 AM PDT by I am Richard Brandon
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To: dr_lew
Just to give some background on how not news this is, this effect was mentioned in the printed text for my Navy electronics school in the module on waveguides. This was in 1982.
29 posted on 09/02/2017 8:50:14 AM PDT by ComradeBork (Consistency is the hobgoblin...)
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To: 2ndDivisionVet

“Still, this research might have engineering applications.”

Can you hear me now?

5.56mm


30 posted on 09/02/2017 8:56:13 AM PDT by M Kehoe
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To: 2ndDivisionVet

https://en.m.wikipedia.org/wiki/Faster-than-light#Group_velocities_above_c


31 posted on 09/02/2017 9:00:41 AM PDT by kosciusko51
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To: BigEdLB

32 posted on 09/02/2017 12:05:04 PM PDT by mikrofon (Labor Day BUMP)
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To: I am Richard Brandon

Oh, I love it...another BTTF fan. :)


33 posted on 09/02/2017 4:07:28 PM PDT by freepertoo
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To: Wu

The relativistic limit is most carefully expressed by saying that information can not be transmitted faster than the speed of light.

If one imagines a pair of scissor blades, or more simply a “guilliotine blade” falling along a straight blade, the point of contact may move faster than “C”, but it cannot transmit a signal of “yes or no”, say, from one point to another along this path, as it is all predetermined, you see.

I’m saying that any claim that the speed of light has been exceeded is ultimately equivalent to this example.


34 posted on 09/03/2017 7:47:01 PM PDT by dr_lew (I)
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To: 6SJ7; AdmSmith; AFPhys; Arkinsaw; allmost; aristotleman; autumnraine; bajabaja; ...
Note: this topic is from 09/02/2017. Thanks 2ndDivisionVet.

· String Theory Ping List ·
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35 posted on 10/23/2017 8:21:32 PM PDT by SunkenCiv (www.tapatalk.com/groups/godsgravesglyphs/, forum.darwincentral.org, www.gopbriefingroom.com)
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To: SunkenCiv

They’ll most likely find out their measurement devices were in error and go back to the drawing board.


36 posted on 10/23/2017 8:26:08 PM PDT by Bullish (Whatever it takes to MAGA)
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To: dr_lew
"If one imagines a pair of scissor blades, or more simply a 'guilliotine blade' falling along a straight blade, the point of contact may move faster than 'C', but it cannot transmit a signal of “yes or no”, say, from one point to another along this path,"

An excellent example of a non-material "thing" moving faster than the speed of light, but is this the effect that they are measuring in their experiment? From the article I couldn't tell what was being done.

It sort of sounded to me like they were measuring two component waves of their overall sound starting at the peak of one component and then declaring the end to be the second component's peak - and then by adjusting the second component's form (moving its peak forward) they come up with a "speed" that is faster than c but really isn't a measure of anything real at all other than the relationship between two manipulated wave forms.

Kind of like moving the finish line forward in the 100 yd dash and then saying you set a new world's record. I hope the "scientists" had to spend their own money on their pvc pipes but I'd be willing to bet it was govt money financing this very important work.
37 posted on 10/23/2017 8:54:21 PM PDT by Garth Tater (Gone Galt and I ain't coming back.)
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To: Bullish

"Stop Messing about with the speeds!"



Graham Chapman

38 posted on 10/23/2017 10:00:30 PM PDT by SunkenCiv (www.tapatalk.com/groups/godsgravesglyphs/, forum.darwincentral.org, www.gopbriefingroom.com)
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To: SunkenCiv

Let’s not go to Camelot... It’s a silly place.


39 posted on 10/23/2017 10:02:02 PM PDT by Bullish (Whatever it takes to MAGA)
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To: Bullish

;’)

http://mms.businesswire.com/bwapps/mediaserver/ViewMedia?mgid=34692&vid=5&download=1


40 posted on 10/23/2017 11:41:35 PM PDT by SunkenCiv (www.tapatalk.com/groups/godsgravesglyphs/, forum.darwincentral.org, www.gopbriefingroom.com)
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