Greg Egan - Luminous

I have to admit upfront that I am a big fan of Greg Egan - I think he is one of the best writers of hard science fiction. This book contains 10 stories, I can see most of them as kind of Gedankenexperiments where he uses some more or less fancy ideas and in a playful way explores the results of these ideas, often by contrasting the new ideas with some conservative forces, more closely resembling our current world views, inside the stories.

These ones I like best:

• Luminous Basing on the Gödel incompleteness theorem, what if mathematical statements become only true or false in the moment a physical realization in the universe forces it to decide? And therefore, many statements are still out the and not yet decided. Then you could do new calculations and by that force decisions on the truth of these statements, push boundaries between true and false ...

On a side issue, he also mentions the computer Luminous which is base solely on the interaction of light rays: for any specific computation, a new pattern of rays is 'compiled' and then implemented to run the program ...

• Mister Volition Here the author plays with ideas of current scientists on the topic of consciousness: an individual tries to find the inner self which does the decisions in his life - but maybe there simply is nothing like this? Actually, I believe this to be true ...

• Transition Dreams A wonderful story, also about consciousness. If the consciousness, the experience of the inner self, is based on physical/physiological processes - as for example the influence of drugs or injuries to our brain suggest -, these physiological processes are our consciousness. So for example if these processes are simulated, the consciousness should happen. If one could hypothetically transfer the processes from body to machine, the buildup of these processes should be consciousness building up and dreaming probably strange transition dreams. Or if the being is decaying ...

• Reasons to be Cheerful From all of these, this is my favorite. Why are we happy? Is it a physiological state, so and so much of that hormone? In this story, this is played through various levels, looking at the feeling of our self, free will against determinism and all. In the beginning we see an individuum having always a high level of a certain neurotransmitter - always being cheerful. After an operation to fix this, he is devoid from all possibilities to feel satisfaction - superbly pictured. On the last level, another surgary will result in the possibility that he himself can choose to enjoy whatever he wants to enjoy ...

• The Planck Dive Plays in a world where bodies are not necessary anymore, humans can be uploaded, transported etc. A group of scientists is planning the dive into a black hole, and proceeding with it.

The complete text of this story is available online on the homepage of the author.

I can highly recommend this book, if you like thought provoking stories!