advice
Greetings Time-Nuts!
I'm a physics theorist interested in performing an experiment to measure
the gravitational time dilation beneath the surface of the Earth. Boulby
Labs in the UK is 1.1 km down which would generate a time differential from
the surface on the order of 1 part in 10^15 -- not much to work with!
I've investigated measuring redshift/blueshift from lasers but our
wavemeter technology is no where near accurate enough. I've concluded that
my best solution is to use atomic clocks, of which I know very little
about. I thought a clock-enthusiast mail group would be a fantastic way for
me to learn about the subject as well as possibly spur ideas on the lab
test design itself.
Thanks in advance!!
Rhoderick Beery
direct: 402-817-9363
Hi,
Have you been in touch with Fermi-Lab? They run a neutrino experiment with a receiver somewhere underground in Wisconsin. At least that's what I recall. I used to live next to a Physics professor who has a minor part in the experiment. I'm not even sure what sort of data they collect there; whether it's time or something else.
Bob Stewart (Not a physicist)
From: Rhoderick Beery <rjbeery@gmail.com>
To: time-nuts@febo.com
Sent: Tuesday, February 21, 2017 11:13 AM
Subject: [time-nuts] advice
Greetings Time-Nuts!
I'm a physics theorist interested in performing an experiment to measure
the gravitational time dilation beneath the surface of the Earth. Boulby
Labs in the UK is 1.1 km down which would generate a time differential from
the surface on the order of 1 part in 10^15 -- not much to work with!
I've investigated measuring redshift/blueshift from lasers but our
wavemeter technology is no where near accurate enough. I've concluded that
my best solution is to use atomic clocks, of which I know very little
about. I thought a clock-enthusiast mail group would be a fantastic way for
me to learn about the subject as well as possibly spur ideas on the lab
test design itself.
Thanks in advance!!
Rhoderick Beery
direct: 402-817-9363
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Hi!
Take a look at http://www.leapsecond.com/great2005/ and
http://www.leapsecond.com/great2016a/
Edésio
On Tue, Feb 21, 2017 at 11:13:34AM -0600, Rhoderick Beery wrote:
Greetings Time-Nuts!
I'm a physics theorist interested in performing an experiment to measure
the gravitational time dilation beneath the surface of the Earth. Boulby
Labs in the UK is 1.1 km down which would generate a time differential from
the surface on the order of 1 part in 10^15 -- not much to work with!
I've investigated measuring redshift/blueshift from lasers but our
wavemeter technology is no where near accurate enough. I've concluded that
my best solution is to use atomic clocks, of which I know very little
about. I thought a clock-enthusiast mail group would be a fantastic way for
me to learn about the subject as well as possibly spur ideas on the lab
test design itself.
Thanks in advance!!
Rhoderick Beery
direct: 402-817-9363
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Hi Rhoderick,
Check your estimates -- for 1 km the redshift should be 1e-13, not 1e-15.
The experiment is certainly possible. It's been done many times -- going up, and going down -- though usually above MSL. Doing it below MSL is on my TODO list; using either mine shaft (land) or bathysphere (sea). The logistics are a bit more complicated than driving clocks up a mountain. You can contact me directly for more info.
To get an idea of how these experiments are done, see:
http://leapsecond.com/great2016a/
http://leapsecond.com/great2005/
http://leapsecond.com/ptti2006/
/tvb
----- Original Message -----
From: "Rhoderick Beery" rjbeery@gmail.com
To: time-nuts@febo.com
Sent: Tuesday, February 21, 2017 9:13 AM
Subject: [time-nuts] advice
Greetings Time-Nuts!
I'm a physics theorist interested in performing an experiment to measure
the gravitational time dilation beneath the surface of the Earth. Boulby
Labs in the UK is 1.1 km down which would generate a time differential from
the surface on the order of 1 part in 10^15 -- not much to work with!
I've investigated measuring redshift/blueshift from lasers but our
wavemeter technology is no where near accurate enough. I've concluded that
my best solution is to use atomic clocks, of which I know very little
about. I thought a clock-enthusiast mail group would be a fantastic way for
me to learn about the subject as well as possibly spur ideas on the lab
test design itself.
Thanks in advance!!
Rhoderick Beery
direct: 402-817-9363
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Hi Bob and Rhoderick,
I believe the experiment you're talking about is MINOS. If there are any
specific questions regarding this, I can probe around. I work (indirectly)
with a professor and his group that is a collaborator with MINOS and
FermiLab. When I have some free time I will ask him about it; seems like
something I would be interested in too.
Ray Xu (more of an engineer, but a "physicist-in-training")
On Tue, Feb 21, 2017 at 1:48 PM, Bob Stewart bob@evoria.net wrote:
Hi,
Have you been in touch with Fermi-Lab? They run a neutrino experiment
with a receiver somewhere underground in Wisconsin. At least that's what I
recall. I used to live next to a Physics professor who has a minor part in
the experiment. I'm not even sure what sort of data they collect there;
whether it's time or something else.
Bob Stewart (Not a physicist)
From: Rhoderick Beery <rjbeery@gmail.com>
To: time-nuts@febo.com
Sent: Tuesday, February 21, 2017 11:13 AM
Subject: [time-nuts] advice
Greetings Time-Nuts!
I'm a physics theorist interested in performing an experiment to measure
the gravitational time dilation beneath the surface of the Earth. Boulby
Labs in the UK is 1.1 km down which would generate a time differential from
the surface on the order of 1 part in 10^15 -- not much to work with!
I've investigated measuring redshift/blueshift from lasers but our
wavemeter technology is no where near accurate enough. I've concluded that
my best solution is to use atomic clocks, of which I know very little
about. I thought a clock-enthusiast mail group would be a fantastic way for
me to learn about the subject as well as possibly spur ideas on the lab
test design itself.
Thanks in advance!!
Rhoderick Beery
direct: 402-817-9363
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/
mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/
mailman/listinfo/time-nuts
and follow the instructions there.
On Tuesday, February 21, 2017 11:13:34 AM Rhoderick Beery wrote:
Greetings Time-Nuts!
I'm a physics theorist interested in performing an experiment to measure
the gravitational time dilation beneath the surface of the Earth. Boulby
Labs in the UK is 1.1 km down which would generate a time differential
from
the surface on the order of 1 part in 10^15 -- not much to work with!
I've investigated measuring redshift/blueshift from lasers but our
wavemeter technology is no where near accurate enough. I've
concluded that
my best solution is to use atomic clocks, of which I know very little
about. I thought a clock-enthusiast mail group would be a fantastic way
for
me to learn about the subject as well as possibly spur ideas on the lab
test design itself.
Thanks in advance!!
Rhoderick Beery
direct: 402-817-9363
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the
instructions there.
Rhoderick
If you have a dark fiber or 2 between the surface and the lab and a pair of
sufficiently stable lasers (one at the surface and one in the underground
lab) you could look at the change in beat frequency between the lasers
(around 50Hz for a pair of red lasers).
Bruce
Neutrinos? Look up the OPERA experiment that measured neutrinos going
faster than light. Turned out to be a loose optical fiber connector to a
timing instrument.
Fermi Lab has/had the MINOS experiment going 500 miles from Chicago to a
mine in northern Minnesota. The generated neutrinos go through Wisconsin
but are not noticed there, AFAIK.
Bill Hawkins (Resident of Minnesota, but not a physicist, just a BSME)
-----Original Message-----
From: Bob Stewart
Sent: Tuesday, February 21, 2017 1:48 PM
Hi,
Have you been in touch with Fermi-Lab? They run a neutrino experiment
with a receiver somewhere underground in Wisconsin. At least that's
what I recall. I used to live next to a Physics professor who has a
minor part in the experiment. I'm not even sure what sort of data they
collect there; whether it's time or something else.
Bob Stewart (Not a physicist)
In the confusion, I forgot that we are concerned with gravitational time
dilation, not time of flight.
The University of Minnesota has a lab about 2500 feet down in the Soudan
mine. The following is their brief description:
"The Soudan Underground Laboratory is a general-purpose science
facility, which provides the deep underground environment required by a
variety of sensitive experiments."
Here's a link to the Soudan page:
https://www.physics.umn.edu/outreach/soudan/tour/
Why is it named Soudan? The original miners found northern Minnesota to
be extremely cold at times, so they named the town for someplace warm.
Let me know if you are seriously considering this, and I will find a
contact for you.
Bill Hawkins
-----Original Message-----
From: Bill Hawkins [mailto:bill.iaxs@pobox.com]
Sent: Tuesday, February 21, 2017 8:08 PM
Neutrinos? Look up the OPERA experiment that measured neutrinos going
faster than light. Turned out to be a loose optical fiber connector to a
timing instrument.
Fermi Lab has/had the MINOS experiment going 500 miles from Chicago to a
mine in northern Minnesota. The generated neutrinos go through Wisconsin
but are not noticed there, AFAIK.
Bill Hawkins (Resident of Minnesota, but not a physicist, just a BSME)
-----Original Message-----
From: Bob Stewart
Sent: Tuesday, February 21, 2017 1:48 PM
Hi,
Have you been in touch with Fermi-Lab? They run a neutrino experiment
with a receiver somewhere underground in Wisconsin. At least that's
what I recall. I used to live next to a Physics professor who has a
minor part in the experiment. I'm not even sure what sort of data they
collect there; whether it's time or something else.
Bob Stewart (Not a physicist)
Review the theory and results in this paper:
http://science.sciencemag.org/content/329/5999/1630?variant=full-text&sso[1]
For small height changes on the surface of Earth, a clock that is higher
by a distance ∆h runs faster by ...
The gravitational shift corresponds to a clock shift of about 1.1 ×
10−16 per meter of change in height.
Bill Byrom N5BB
On Tue, Feb 21, 2017, at 11:13 AM, Rhoderick Beery wrote:
Greetings Time-Nuts!
I'm a physics theorist interested in performing an experiment
to measure
the gravitational time dilation beneath the surface of the
Earth. Boulby
Labs in the UK is 1.1 km down which would generate a time differential
from
the surface on the order of 1 part in 10^15 -- not much to work with!
This short paper was issued by NIST researchers in 2010, and it
discusses making accurate gravitational time dilation / redshift
measurements using lasers:
http://tf.boulder.nist.gov/general/pdf/2447.pdf
Quoting that paper:
Differences in gravitational potential can be detected by comparing
the tick rate of two clocks. For small height changes on the surface
of Earth, a clock that is higher by a distance Δh runs faster by
Δf/fo = g Δh/c2
where g ≈ 9.80 m/s2 is the local acceleration due to gravity. The
gravitational shift corresponds to a clock shift of about 1.1 × 10−16
per meter of change in height.
So at your laboratory depth of 1.1 km, the fractional frequency change
should be about:
1.2 x 10-13 (1.2 parts in 10^13)
--
Bill Byrom N5BB
On Tue, Feb 21, 2017, at 11:13 AM, Rhoderick Beery wrote:
I'm a physics theorist interested in performing an experiment
to measure
the gravitational time dilation beneath the surface of the
Earth. Boulby
Labs in the UK is 1.1 km down which would generate a time differential
fromthe surface on the order of 1 part in 10^15 -- not much to
work with!