Sunday, February 24, 2008

Happy Birthday, Backreaction!

Two years ago, I received a very short email from Sabine: She invited me to join her new blog, and to have a look at her first post about "Risky Black Holes". This was the birthday of "backreaction"!

I didn't expect at all what has followed: Over the next few months, we've somehow found our own way to run the blog, and in the two years since February 2006, we - mostly Sabine, actually - have written a bit more than 500 posts. We have won a few regular readers, received thousands of interesting comments, and had lots of enlightening discussions. Thank you to all of you who appreciate our writing and contribute your insights! I highly appreciate this feedback, even more so because I usually invest quite some time in the preparation of my posts, and every so often wonder why I am actually doing all this.

The really rewarding thing is that you get to know very interesting people for all over the world you never would have met otherwise. And, I should add, running a blog is a great thing you can do together when for some reason, your spouse is living on the other side of the ocean!


  1. Congrats, Stefan and Bee!

  2. how lovely, you took the photo yourself (I bet you didn't make the cake, it looks like you bought it at the Cafe next door). happy birthday, thanks for the sparkling wine :-)


  3. Congrats! I'm really glad that you bother to blog! I hope it remains a labor of love.

  4. Hi Stefan and Bee,

    Congratulations, five hundred posts in two years, it makes the mind spin. As acknowledged you could have only manage such a thing if it were a labour of love. I’ve only been aware of it for a short time and must tell you, that in comparison to anything else of this nature, it far exceeds any of those. As I would be recognized as one of those early adapters you can imagine I have a lot to compare it to. You should realize you haven’t just created an impressive resource, yet also a space that never existed before; a space where people meet to express and exchange their thoughts of hope, ambition and concern. It is also a space where one can expand a little in what they know and understand. Therefore you should be both proud and we should be (and are) grateful.

    Best Wishes,


  5. Congratulations you too.

    "a labour of love"

    Wonderful motivation to help give us that space in the world "focus" and in becoming clearer, an understanding of humanities historical heritage.

    Just when "the vessel seems to become empty," it again becomes full. It just seems to be the way of it, and runners understand it well? Like hitting a wall.

    Sure there are physiological aspects to the euphoria, but there is a deeper consequence even in problem solving. Free the mind?

    Oh, and thanks for putting up with me.:)

  6. Happy Birthday!


  7. Happy Birthday and congratulations on a very interesting blog.

  8. Thanks for all the fun and facts! And trying to make the physics world a better place.

    Best wishes,


  9. Happy Birthday Backreaction / Bee / Stefan! Here is a little gift for the three of you, to help you celebrate. ;-)

  10. Congratulations, Sabine and Stefan!

    Your blog was a delight in the past two years. While some famous bloggers are pompous and haughty toward the readers, which I can feel from their indifferent silence to the comments, our hostess Busy Bee's posts and comments to the comments to her posts were both empathic and intelligent. How can I not love her? (I feel jealous toward Stefan. ;-) But, don't be worried, Stefan. This love is only Platonic.)
    Sabine's recent despair about no progress in her research also strikes a sympathetic bell in me. In our quest to the truths we still remain as hunter-gatherers. Packed as groups in two or three, sometimes alone, we are foraging through woody or barren areas. The journey is mostly exhausting especially when we are not refreshed by sporadic discoveries of wild berries or a pond full of fish. Sometimes we come across other clans or packs who are also in the midst of foraging. We exchange some words of information and go separate ways to continue journeys. Sometimes we enter a village where a large pack of previous hunter-gatherers have settled down. Here we find leaders and laborers, and all kinds of hierarchy. Their quest became a sort of business. We don't feel right or belonged here, so we continue our foraging even thogh the chances of starving to death will be higher when we leave the village. But the sense of independence and loneliness in our unbeaten trail is a much stronger attractant. Thus we leave as Sabine does.
    But Sabine, I want to hear from you from time to time regardless of success or failure of your quest. And also be aware that there are lots of lonely foragers hungry to reach some Amazon jungles or coasts of immense oceans. Love to hear from you there, but who knows if I would be there first waiting for you to arrive? ;-)

  11. Here's a QTVR panorama of the "wedding cake" building @Caltech:

    Has purple flowers, which coincidentally match the purple in the birthday cake.

    Is this how you met, which ended in marriage?

    I shot the 2/20 Lunar Eclipse:

    I was fantasizing in my recent astro-trips, about taking you (B+Stefan) along as guests.

    More panos at:

  12. Hi all,

    thanks for the kind words! The cake was form the local Cafe, as Bee has guessed :-). Dear Amara, Changcho, thanks for the photos! BTW, Changcho, we had very bad weather in Frankfurt last week, so I didn't see anything of the eclipse (and didn't have a bad feeling either because I did not set my alarm clock to 3:30 in the morning ;-)...)

    Best, Stefan

  13. Happy Birthday - Keep up the good work!


  14. What is that? It looks delicious.

  15. Happy Birthday, Stefan and Sabine!

  16. Happy birthday, Bee, Stefan, and BR. I'm glad to see that Bee didn't jump out of a window somewhere to celebrate.

  17. Happy Birthday to one of the most interesting blogs on the Internet, and thanks to Bee and Stefan for writing it.

  18. Happy Birthday to you!!!

    I love your blog...

  19. Happy birthday to Backreaction and the fine job the editors has done. It is demanding to edit a science blog and do the day jobs. The readers of this blog do appreciate very much. I have learned much, laughed a few times at the naughty jokes. (Especially the 'math universe' plank.)

    But, alas, it is more important to do the day jobs. Bee has indicated frustration - so I wish you all the best in your research. Take all the time out you need - because it is just as rewarding to hear your thinking and results of your research in Backreaction.

  20. Yes, happy birthday to Backreaction and congrats to the the crew of Bee and Stefan. This blog is informative on physics, can be very deep and thought provoking (e.g. some of Bee's best essays on "issues") and yet still fun. We commenters get to meet interesting people too. It's a hip mix of science pros and some free but sharp-witted spirits.

  21. Happy Birthday, and keep up the good blogging work!

  22. Happy Belated Blogaversary! I don't always understand everything you two write, but I love reading you. Thanks!

  23. Dear all,

    thanks again for the wishes :-)

    And, The Ridger: As everyone else, you're very welcome to ask if something is not clear or understandable to you. To me it's sometimes difficult to judge what I should try to explain in more detail in my posts, and if the explanations I give are too short or too jargon-laden. So, don't be shy, just ask if something about the post interests you and you want to know more, or a better explanation!

    And thanks for pointing out this awesome Astronomy Picture of the Day with the Lunar Eclipse seen from Mauna Kea!

    Best, Stefan



If the number of comments exceeds 200 you must click LOAD MORE at the bottom of the page to see all comments. This is also true for replies to threads. I know this sucks. Please complain to Google about this, not to me.

Comment moderation on this blog is turned on. Submitted comments will only appear after manual approval, which can take up to 24 hours.

Comments posted as "Unknown" go straight to junk. You may have to click on the orange-white blogger icon next to your name to change to a different account.

Note: Only a member of this blog may post a comment.