Space Time Quest
Space Time Quest is a fun game developed by gravitational wave scientists working in the LIGO collaboration (see `A Brief History of Space Time Quest'). The game puts you in charge of designing your own gravitational wave detector. You make choices and trade-off decisions to select the best technology while keeping an eye on the budget. The game is casual but addictive: you can reach the first score (how many gravitational waves did you detect) in just a few minutes. But then you want to go back and try for the highest score, knowing that LIGO scientists are in the gravitational wave high-score hall of fame as well. Can you beat them, literally, at their own game?
Space Time Quest can be played in English, Spanish, Catalan, Dutch, German, Chinese, French, Italian, Russian, Japanese, Hindi and Brazilian Portuguese! If instead you are more interested in studying the underlying equations and Python code, see below for our open source version: Space Py Quest!
How to play
The overall aim of Space-Time Quest is to design a working interferometer to detect gravitational waves from astrophysical sources far, far away. This is accomplished by increasing the sensitivity of our detector allowing us to detect these incredibly faint signals.
One of the main issues with gravitational wave detectors situated on the surface of the Earth is the noise that comes from the environment, and the noise that is always present in the equipment that we to measure the waves. This noise can drown out all of the faint signals from distant gravitational wave sources that we might possibly detect. In order to see these sources we must reduce the noise from all the environmental factors and equipment we use to produce an incredibly sensitive detector. Whilst playing the game you have the ability to experiment with the many different variables that the detector relies upon such as; the power of your laser, the vibration isolation equipment, cryogenic cooling, the location of the detector and many others. All these need to be realistically balanced, not only in performance, but by how much they cost as you don't have an infinite source of money!
Starting the game from the main screen you are first asked to enter your name and a name for your detector. You are then asked to choose one of four options on where you would like your detector to be located. By clicking on each of the locations (City, Desert, Island or Forest) you can see the various attributes of that location. The higher the number of stars for the Noise the quieter that location will be, i.e. less noise from human and seismic activity. The greater the number of budget stars the more money you get to start with.
Now you will enter the Principal Investigator's (PI) office, from which you control the main part of the game. This is the design phase during which you can tweak parameters of the detector in order to make it more sensitive. The sensitivity is determined by sum of various noise contributions. You can always check all the noise curves in the Noise Model screen; this can be opened up at any point by clicking the green graph icon:
You can adjust the subsystem settings while the Noise Model is open and see how the noise in the noise curves change when you change the detectors parameters. The best sensitivity is reached when the total noise, which is the sum of all other curves, is as low as possible over a wide frequency range. You can close the Noise Model by clicking on the green noise model icon again.
From the PI office you can access the design areas for each of the subsystems for your detector. You access each of the subsystems by clicking on each of the monitors on the PI's desk. The following subsystems are available:
- Environment Subsystem: Here you can experiment with various values for the depth of the detector, vacuum system and cryogenic cooling.
- Vibration Isolation: Isolating the experiment's equipment from seismic noise is very important, here you need to design the pendulum system to reduce the noise as much as possible.
- Optics Subsystem: The detector relies on high quality optical equipment. For this subsystem you must experiment with different laser and mirror properties to get the best result.
Once you are in one of the subsystems you can get back to the PI's office at any point by clicking the house icon on the menu bar.
While you are changing parameters and try for the best sensitivity you must watch the remaining budget:
You won't be able to compute a score when you are over budget.
The more you enhance your detector, the more complex the machine becomes. This could make the operation of the detector more difficult and can cause occasional data loss. Thus your number of detections will be slightly lower when you design a very complex machine. You can see the complexity rising in the `Complexometer':
Once you have setup your subsystem settings you then need to begin your 'Science Run' and see how your detector performs. You do this by clicking the science run button on the desk in the PI's office. Once the detector is 'locked', in other words when all control systems have been engaged and are working, you will see how far away our detector can measure gravitational waves from. The gravitational wave sources we are expecting to detect are few and far between, so having a large range gives us a much better chance of detection. Your final score is added to the high score board.
We hope Space Time Quest can be a fun and competitive game. In addition, we wanted the game to provide educational merits, especially when used in conjunction with additional guidance or using complementary online material. The game was written by scientists who used very similar software at work to help design the real gravitational wave detectors such as LIGO and Virgo. With the game we wanted to give people the opportunity to experience this design process themselves.
By playing the game, the user should become familiar with the idea of noise as a fundamental part of performing measurements. The players will explore how individual noise components add up to a total noise level. In order to get a competitive score, they will have to try various different detector configurations, and make judgements on their relative merits based on the sensitivity curve.
As well as learning about some of the specific challenges facing the scientists who design the real gravitational wave interferometers, the players will also learn about spending a large budget wisely, and about making trade-offs between different interlinked subsystem parameters based on the information in the sensitivity curve.
A large fraction of the scientific software in the gravitational wave community is written in Python, a programming language that we also recommend for teaching and leaning scientific computing. With Space Py Quest we provide an open source, Python-based implementation of Space Time Quest. With Space Py Quest you can play the game in a browser based interface (Jupyter notebook), see the screenshot below. Or you can dive into the code, explore the equations behind the noise curves, and learn how we use simple Python scripts for creating scientific models. You can download the code from the Space Py Quest repository at GitHub, and have a look at a SpacePyQuest.pdf, a detailed note documenting the parameters and equations behind the code.
The aim of Space Py Quest is to provide insight into the actual scientific process in the gravitational wave community. The code was written by physics students whose research tasks involved writing Python-based modelling software for the LIGO detector.
You are very welcome to use Space Time Quest in your events or exhibitions. You can download a high-resolution (pdf) version of the flyer below. It shows the URL and QR code for visitors to download the app and show it to their friends.
You may also download and use the images below to help promote the game or your events that makes use of the game. We would love to hear your feedback, for example, how you made use of the game and what additional resources you would find useful.
The game has been developed by a small team in the Gravitational Wave Group in Birmingham. We would like to thank our colleagues in the School of Physics and Astronomy in Birmingham and members of the gravitational wave collaborations for extensive beta testing, generous feedback and support! We are grateful for support from the Alumni Impact Fund of the University of Birmingham which allowed us to port the game to mobile devices in 2017. Further development of the game for science outreach in India has been supported by STFC through the GCRF Capacity Building with LIGO-India project, Ref ST/S000038/1.
— Gravitational Wave Group, University of Birmingham.
- Unity engine