fasTrak's ``SpaceTime Explorer''

For SLAPT visitors, check out these
Extreme Physics Lesson Plans in development
Unit 1: NanoExploration.
Unit 2: One Map, Two Clocks.

[intro] [operation] [challenge] [window on spacetime] [puzzlers] [links] [footnotes]

Below find the ``live remote'' image of a 1 [kg] round blue-green glider on a 10 [meter] track, with yellow timing gates separated by 1 [meter] (gateSep) whose traverse is timed by both lab frame (mapTime) and glider (travTime) clocks. Because this track is capable of high speeds, we had to find someplace to put it with a good vacuum. The Milky Way's interstellar medium (not far from sol and good old planet earth, just outside the Oort cloud) seemed like a good bet. Thanks to web-based telepresence, you don't actually have to put on a space suit and go there because you can control the experiment from the comfort of your home computer! You'll note that we avoid the long-distance communications time lag in this process. Don't ask how.

Operating Instructions

Applet Window Operation: Slide your mouse cursor over the image, and the glider will move quickly past the gates while your view of the model begins to rotate. You can spin and/or zoom in and out on the remote platform, by dragging the mouse and/or shift-dragging the mouse respectively. The glider (also the spinning) can be stopped and restarted with a double-click. When action has been stopped with a double-click, dragging the glider (a little square appears around it) "downstream" from the timing gates (followed by another double-click) repeats the current experiment.

Changing the Kinetic Energy of Launch: While stopped with a double-click, the magenta kinetic energy indicator can also be selected and dragged to new values on its logarithmic scale. This resets the glider, which when restarted at low energies (with another double-click) behaves as one might expect in an everyday lab experiment. At higher energies, mapTime and travTime begin to differ.

Javascript Button Operation: You can also select the speed of the glider with the javascript buttons in the table below the applet window. However, after pushing the buttons you must bring the mouse cursor back over the applet window to run the experiment and read out data on the timers. Note: If nothing happens with the cursor over the window, a double-click should get the experiment back up and running.

The Challenge

Take some data on mapTime and travTime between gates for this glider (the window readouts are in seconds) at different kineticEnergies. Can you come up with a quantitative hypothesis for predicting the observed behavior? Given that things like this do happen in the real world, what does it tell YOU about the nature of space and time in our universe?

Window on SpaceTime

Propose kineticEnergy in [J] ~ :
Propose kineticEnergy in [J] as ~ 10 to the power:
kineticEnergy buttons:
Propose coordVelocity in [mapLightYears/mapYear] ~ :
coordVelocity buttons:
Propose properVelocity in [mapLightYears/travYear] ~ :
properVelocity buttons:


For more on this subject

Other links on flatspace motion at any speed, examined with a collection of co-moving yardsticks and synchronized clocks (i.e. from the vantage point of a reference mapFrame) can be found here. Writeups with references related to this include these notes on anyspeed modeling, modernizing Newton, one-map two-clocks, and anticipation.

Note: In the near future, this remote platform will be shut down briefly to install the capability of mounting a second glider for dynamical studies. A prototype of the two-glider system is already operational. Two dimensional computer-simulations of these phenomena, and of related spacetime experiments in ours and/or other universes, can be found here. Look here for a link to notes on use of this equipment for modeling-workshop style high school and college classroom exercises shortly. If instead you'd like to examine a wider range of physical objects in this corner of the universe, you might enjoy playing with the powers of ten explorer inspired by this remote sensing project, or our new quantum relativistic powers of spin explorer here.

This page is Acknowledgement is due particularly to Martin Kraus for his robust Live3D applet. The galactic panorama is copyright Axel Mellinger, and is adapted here with permission, from his 300MB All-Sky Milky-Way. Although there are many contributors, the person responsible for errors is P. Fraundorf. This site is hosted by the Department of Physics and Astronomy at UM-StL. MindQuilts site page requests ~2000/day approaching a million per year. Requests for a "stat-counter linked subset of pages" since 4/7/2005: .