I have a joke I do from time to time where I announce I’m a time traveller. I can travel forward in time!
Specifically, I can travel forward in time at a rate of one second per second. 
(I didn’t say it was a good joke).
And that got me thinking - is there a unit for “seconds per second” in the context of moving through time at a rate faster or slower than normal?
Not exactly the most profound question in the world, but I’m curious.
Radians.
“Times faster than normal”
As in: “we traveled to the future for 30 seconds, about a million times faster than normal, skipping about 1 year.
Am I missing something?: seconds squared, no?
Yes, you’re missing something. Seconds squared would come from seconds times seconds. As presented, the units are essentially seconds divided by seconds, a simple unitless ratio.
English and math don’t work together perfectly. You might be confusing the statement given with, say, the units typically given for the acceleration of gravity, 32 feet per second per second. There, the ‘per second per second’ does indeed mean ‘per second squared’, but that expression only works with both ‘per’ words in place – it really boils down to a quirk of language.
Okay… try this one more time. I’ve revised and bolded words from my previous post.
English and math don’t work together perfectly. You might be confusing the statement given with, say, the units typically given for the acceleration of gravity, 32 feet per second per second. There, the ‘second per second’ might seem to mean ‘second squared’, but that expression only works with both ‘per’ words in place – it really boils down to a quirk of language.
Hertzy McHertzface
Seconds divided by seconds just gives you a unitless percentage. In mechanics, we define *strain *(compression or elongation) as inches per inch, or mm per mm. In either case, it just reduces to a percentage, such as “strain of .01” meaning an elongation of one inch per 100 inches of original length. I would think a time traveler could use a similar metric.
Of course it won’t do your joke any favors, if you have to refer to your time traveling ability as a time strain of 1.0.
Thank you all!
I don’t think that there is a current unit like this, but it’s the sort of situation that historically gets named after a person, like the Mach number, the Reynolds number, the Planck constant, the Richter scale, the Chandrasekhar limit. So your best bet would probably be to take the time machine inventor’s name and Machify it: ‘we’re traveling forward at Venkatisan 12.5’. Or you could go with “Time Factor” from the old Star Trek pilot.
And of course, a speed of 1 second per second is c. In a sense, we’re all moving at the Speed of Light; we’re just doing so almost entirely in the time direction.
It’s not a percentage until you multiply by 100. Without that multiplication it’s a dimensionless ratio.
Your joke is actually a standard response by physicists when asked about how fast time is moving in a given frame of reference. It’s always 1 second per second. No matter where you go, there you are.
There is no such thing as “normal” when it comes to the passage of time (viz. Special Relativity). There is no one particularly privileged frame of reference. You might say, “We experienced 30 seconds of time but on the surface of the Earth they experienced 1 year.”
How about Hertz-seconds?
1 hertz-second = 1 second per second.
The reference frame would part of the units in this case, right? E.g. “0.1 spaceship seconds per Earth second”.
How about you travel forward in time at the rate of 60 seconds/minute?
[Buckaroo Banzai] And no matter where you are, there you go [/BB]