Philosophy Now Forum

Ginkgo wrote: No, it is actually relevant. I found this very good explanation:

Einsteins Special and General Relativity in Everyday Life.

But in a relativistic world, things are not simple. The satellite clocks are moving at 14,000 km/hr in orbits that circle the Earth twice per day, much faster than clocks on the surface of the Earth, and Einstein's theory of special relativity says that rapidly moving clocks tick more slowly, by about seven microseconds (millionths of a second) per day.

Also, the orbiting clocks are 20,000 km above the Earth, and experience gravity that is four times weaker than that on the ground. Einstein's general relativity theory says that gravity curves space and time, resulting in a tendency for the orbiting clocks to tick slightly faster, by about 45 microseconds per day. The net result is that time on a GPS satellite clock advances faster than a clock on the ground by about 38 microseconds per day.

This is the relevant bit from the physics website. In fact you can find this information on any physics website.

Hobbes' Choice wrote:

Ginkgo wrote: No, it is actually relevant. I found this very good explanation:

Einsteins Special and General Relativity in Everyday Life.

But in a relativistic world, things are not simple. The satellite clocks are moving at 14,000 km/hr in orbits that circle the Earth twice per day, much faster than clocks on the surface of the Earth, and Einstein's theory of special relativity says that rapidly moving clocks tick more slowly, by about seven microseconds (millionths of a second) per day.

Also, the orbiting clocks are 20,000 km above the Earth, and experience gravity that is four times weaker than that on the ground. Einstein's general relativity theory says that gravity curves space and time, resulting in a tendency for the orbiting clocks to tick slightly faster, by about 45 microseconds per day. The net result is that time on a GPS satellite clock advances faster than a clock on the ground by about 38 microseconds per day.

This is the relevant bit from the physics website. In fact you can find this information on any physics website.

In other words what I said was correct. Altitude means that clocks will travel at different velocity and this affects the time.
What was irrelevant is you pointing out the "difference" between general and special.

Ginkgo wrote:

Hobbes' Choice wrote:

Ginkgo wrote: No, it is actually relevant. I found this very good explanation:

Einsteins Special and General Relativity in Everyday Life.

But in a relativistic world, things are not simple. The satellite clocks are moving at 14,000 km/hr in orbits that circle the Earth twice per day, much faster than clocks on the surface of the Earth, and Einstein's theory of special relativity says that rapidly moving clocks tick more slowly, by about seven microseconds (millionths of a second) per day.

Also, the orbiting clocks are 20,000 km above the Earth, and experience gravity that is four times weaker than that on the ground. Einstein's general relativity theory says that gravity curves space and time, resulting in a tendency for the orbiting clocks to tick slightly faster, by about 45 microseconds per day. The net result is that time on a GPS satellite clock advances faster than a clock on the ground by about 38 microseconds per day.

This is the relevant bit from the physics website. In fact you can find this information on any physics website.

In other words what I said was correct. Altitude means that clocks will travel at different velocity and this affects the time.
What was irrelevant is you pointing out the "difference" between general and special.

Moving clocks tick slower. Special relativity.

Clocks above the earth experience weaker gravity-they tick faster. General relativity.

GPS satellites are both moving and above the earth so special and general relativity have to be taken into account.

Ginkgo wrote:They don't cancel each other out if this is what you mean.

Ginkgo wrote:

duszek wrote:Velocity (or speed) is defined by time.
Time is one of the defining elements.

It is for example 100 miles per hour.

Instead of time we could take sunsets and also express velocity:

I move 10 miles per 3 sunsets.

In relation to your original question. Yes, people on mountains live and more more quickly than people living at sea level.It all depend on the reference frame. People on mountains who live and more more quickly don't notice the difference because their metabolism also keeps pace with faster time.

The important point is there is not absolute time, regardless how we choose to measure it.

Ginkgo wrote:

Moving clocks tick slower. Special relativity.

Clocks above the earth experience weaker gravity-they tick faster. General relativity.

GPS satellites are both moving and above the earth so special and general relativity have to be taken into account.

duszek wrote:

Ginkgo wrote:

duszek wrote:Velocity (or speed) is defined by time.
Time is one of the defining elements.

It is for example 100 miles per hour.

Instead of time we could take sunsets and also express velocity:

I move 10 miles per 3 sunsets.

In relation to your original question. Yes, people on mountains live and more more quickly than people living at sea level.It all depend on the reference frame. People on mountains who live and more more quickly don't notice the difference because their metabolism also keeps pace with faster time.

The important point is there is not absolute time, regardless how we choose to measure it.

But if the reference frame is the rising and the setting of the sun (or the chanting of a rooster) then time does not move faster in the mountains.

And their metabolism does not move faster either.

duszek wrote:

Ginkgo wrote:

Moving clocks tick slower. Special relativity.

Clocks above the earth experience weaker gravity-they tick faster. General relativity.

GPS satellites are both moving and above the earth so special and general relativity have to be taken into account.

All kind of clocks tick faster in the mountains ?

duszek wrote:They cannot tick at the same rate.
Those depending on gravitation tick at different rates, depending on how far from the center of the earth they are.

Those not depending on gravitation (or depending on a different centre of gravity) have their own rate.

That´s the whole point.

duszek wrote:What do you mean by "ticking at the same rate" ?

If one person were watching the clock on the beach and another one were watching the clock on the mount and if after 10 days they compared how much "time" had passed so far the results would be a tiny little bit different. They could communicate by a mobile phone and compare what they see.

surreptitious57 wrote:The speed of light in vacuum is a constant but time and space are not. This is why the fabric of spacetime can be distorted by General
Relativity with regard to the gravitational force exerted by massive objects such as stars. Far as time is concerned a moving clock uses
up more energy than a static one. For objects approaching light speed time would physically stop. Though this is actually impossible as
infinite mass would occur too. And infinities in physics when applied to reality are meaningless. And this is why the singularity which is
supposed to be at the beginning of the Big Bang is problematic. As it references not one but two of them : the negative infinity of zero
volume and the positive infinity of infinite mass. Infinities are fine in maths but do not translate to reality as that is finite by definition