Completely change the strategy of the age old game of chess with quantum physics!
All Reviews:
Mostly Positive (19) - 73% of the 19 user reviews for this game are positive.
Release Date:
Feb 28, 2017

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Early Access Game

Get instant access and start playing; get involved with this game as it develops.

Note: This Early Access game is not complete and may or may not change further. If you are not excited to play this game in its current state, then you should wait to see if the game progresses further in development. Learn more

What the developers have to say:

Why Early Access?

“Early access will allow players a chance to get their hands dirty with quantum phenomena now, and will help us build a more stable and higher quality finished product. Testing feedback will help us find and squash bugs and refine features, and could lead to the addition of highly desired features.”

Approximately how long will this game be in Early Access?

“The game should be in early access for approximately 2-3 months before it is released.”

How is the full version planned to differ from the Early Access version?

“For the finished product we want to implement a leader board and intelligent matchmaking, social media integration, a personal collection of different chess set styles to show off in online games, and an in game store to acquire new sets.”

What is the current state of the Early Access version?

“The game is currently in an ALPHA state. With early access players will be able to play a working version of the game that includes Offline play (side-by-side or against an admittedly dumb AI), a Tutorial, and Online games against other players. Early access players will gain access to new features as they are added moving toward release, and will receive the full release version. The best way for early access players to learn to play is probably through Online games.

There are bugs. Your participation will help us find and squash them!”

Will the game be priced differently during and after Early Access?

“There is currently no plan to change price as we leave early access, but the addition of new features could change this.”

How are you planning on involving the Community in your development process?

“We have an active Discord server through which we can interact with the community and receive valuable feedback. We will also be active on the Steam discussion boards.”
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Recent updates View all (17)

February 15

Phase Indicator

Relative phase is an important concept in quantum physics because it can change the outcome of an operation through interference. In Quantum Chess, moves are unitary operations, and their outcomes can change if the underlying state has certain phase characteristics.

Until now the player has only been presented with probability information. This could lead to confusing situations where moves appeared to have no effect. After some careful thought, and some math, the game can now display some basic relative phase information. It isn't complete, but it should be relevant to a lot of moves. Here is an example.

The Merge move is designed to undo a Split move. If used immediately after a split it should result in 100% of the piece being in the target square (assuming there are no pieces blocking the paths). Here we can see how it acts on the queen.

Notice the yellow lines on the queens involved in the move are pointing in the same direction. We call this being "in phase".

Now if we perform a Standard move for the queen in d2, moving it to d3, and then perform the Merge move, we get something different.

Notice that the standard move has caused the yellow lines to no longer point in the same direction. The piece that was moved picked up a relative phase of pi/2 compared to the one that didn't move.

Phase can be a complex topic. But if you play around with moves, and take notice of how the phase indicators relate to each other, you can gain an intuition for how it will change the outcomes. This is the first successful attempt at getting meaningful phase information into the game, and it will likely evolve.

I can't wait to get this out there for people to play with!
0 comments Read more

February 9

Split and Merge Moves

Hey everyone, I wanted to show you what the new quantum moves will be like when the next version is released. As stated previously the "double" move will be going away. It will be replaced by two quantum moves.

The Split move will allow a piece to split and occupy two different positions. This is similar to the "double" move except there is no possibility that the piece didn't move, and it can only reach one standard move away.

The Merge move is designed to undo a Split. The player will select two squares with the same type of piece, then select a single "target" that is reachable by both.

You can also see the experimental phase indicator in these gifs (more on that later)!
2 comments Read more
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About This Game

Dive into the strange world of quantum mechanics in the game of Quantum Chess, the game you saw in Caltech IQIM's "Anyone Can Quantum" where Paul Rudd beat Stephen Hawking. With the addition of the Quantum Move players can position a single piece in multiple locations on the board at once! This puts a whole new spin on standard chess strategy, and allows everyone to get hands on with quantum phenomena like superposition and entanglement. Play against the computer, or pit your new found mastery against your friends in an Online match.

System Requirements

Mac OS X
SteamOS + Linux
    • OS: 7, 8, 10
    • Processor: 1 GHz
    • Memory: 2 GB RAM
    • Network: Broadband Internet connection
    • Storage: 1 GB available space
    • OS: 7, 8, 10
    • Processor: 2 GHz
    • Memory: 8 GB RAM
    • Network: Broadband Internet connection
    • Storage: 4 GB available space
    • OS: Snow Leopard or better
    • Processor: 1GHz
    • Memory: 2 GB RAM
    • Storage: 1 GB available space
    • OS: Ubuntu or equivalent
    • Processor: 1GHz
    • Memory: 2 GB RAM
    • Storage: 1 GB available space

What Curators Say

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