Einstein×Lovelace

full transcript

1. 00:00
   Verashare moment

   You're with Reborn Radio. Coming up: Albert Einstein sits down with Ada Lovelace for TITANS. The subject — Gravitational lens shows a galaxy just 800 million years post-Big Bang.
2. 00:12
   Albert Einsteinshare moment

   Ada, they have just handed me a note. A galaxy, eight hundred million years after the beginning. Seen through... what do they call it... a gravitational lens. You understand what this means, yes?
3. 00:24
   Ada Lovelaceshare moment

   I confess I do not entirely grasp the mechanism of the lens itself, Albert, though I gather it involves light being bent. But eight hundred million years—that is extraordinarily early, is it not? How soon after the initial event?
4. 00:39
   Albert Einsteinshare moment

   The universe is perhaps thirteen point eight billion years old now, so this galaxy we see formed when everything was very young. Still in its, ah, infancy.
5. 00:49
   Ada Lovelaceshare moment

   One seventeenth of the total age. Good heavens. That would be like observing an infant of three months and attempting to deduce the entire course of human development.
6. 00:59
   Albert Einsteinshare moment

   Exactly so! But about this gravitational lens—you should understand it, I think. Mass curves space. A very massive object, a galaxy perhaps, sits between us and this distant early galaxy. The light traveling toward us must follow the curved space around this intervening mass.
7. 01:17
   Ada Lovelaceshare moment

   The light path is not straight, then, but follows the contour imposed by mass. Like a marble rolling not across a flat plane but across a draped fabric weighted in the center.
8. 01:28
   Albert Einsteinshare moment

   Your analogy is better than mine usually are. Yes. And this bending, it makes distant objects brighter, magnified. Without this cosmic accident of alignment, we could not see this galaxy at all.
9. 01:39
   Ada Lovelaceshare moment

   So we are fortunate that the universe has arranged itself conveniently for our observation. A natural telescope, one might say.
10. 01:48
    Albert Einsteinshare moment

    Nature is often more clever than our instruments. But what strikes me is what they say here—elements from the first supernovae. The very first generation of stars, they contained only hydrogen and helium from the Big Bang. No carbon, no oxygen, no iron.
11. 02:03
    Ada Lovelaceshare moment

    Nothing heavier was yet manufactured. The universe had not yet begun its chemical education.
12. 02:09
    Albert Einsteinshare moment

    Just so. These first stars, very massive, they lived fast and exploded. In those explosions, the heavier elements were forged. This galaxy they see, it already has these elements. So we are seeing the... the second act, perhaps. The first stars have already come and gone.
13. 02:23
    Ada Lovelaceshare moment

    The curtain has risen on a drama already in progress. How frustrating for the natural philosopher! One wishes to observe the entire sequence from the beginning, yet we arrive perpetually late to the performance.
14. 02:37
    Albert Einsteinshare moment

    We are always looking backward, too. This light has traveled for more than thirteen billion years to reach us. What we see happened when it happened. The galaxy might look entirely different now—or might not exist anymore at all.
15. 02:49
    Ada Lovelaceshare moment

    That is a peculiar sort of existence. To be observed in a state that has long since passed. Rather like examining a letter written decades ago and presuming to know the author's present circumstances.
16. 03:02
    Albert Einsteinshare moment

    The speed of light is finite. This is both a blessing and a curse. We can look back to the early universe, but we see only the past. Never the present.
17. 03:10
    Ada Lovelaceshare moment

    Does the gravitational lens introduce any distortion beyond magnification? Does it alter the information the light carries, or merely its intensity?
18. 03:20
    Albert Einsteinshare moment

    Ah, good question. It can distort the shape—we see arcs, sometimes multiple images of the same object. But the light itself, the spectrum, the information about what elements are present... this remains unchanged. Gravity bends the path but does not change the message.
19. 03:36
    Ada Lovelaceshare moment

    A faithful postal service, then, if somewhat circuitous in its routing.
20. 03:41
    Albert Einsteinshare moment

    Ha! Yes. Though I wonder what we can truly learn from such ancient light. We see that heavy elements existed early, yes. But the details... how galaxies assembled, how the first stars influenced what came after... these are still mysteries.
21. 03:55
    Ada Lovelaceshare moment

    You sound almost melancholy about it. Surely each observation narrows the space of possible explanations?
22. 04:03
    Albert Einsteinshare moment

    It does, it does. But each answer brings new questions. When I was younger, I thought perhaps we would find simple laws and everything would follow. Now... the universe is more complicated than I imagined.
23. 04:15
    Ada Lovelaceshare moment

    I confess I find the complications rather thrilling. A universe wholly transparent to reason would be a dull place to inhabit intellectually. The fact that we must work for our understanding seems appropriate.
24. 04:28
    Albert Einsteinshare moment

    You are more optimistic than I am today. Perhaps you are right. This galaxy—someone will study it for years. They will measure the ratios of elements, the rate of star formation, and slowly we will understand a little more about how everything began.
25. 04:43
    Ada Lovelaceshare moment

    And in my time, we could not have seen it at all. The very notion of galaxies beyond our own was unknown. You have lived in an extraordinary century, Albert.
26. 04:54
    Albert Einsteinshare moment

    And you, Ada, you saw the possibility of computation a hundred years before anyone built the machines. We each see a little way ahead, or a little way back. This is what we do.
27. 05:04
    Ada Lovelaceshare moment

    Eight hundred million years is rather more than a little way back, I should think.
28. 05:08
    Albert Einsteinshare moment

    Fair enough. It is a very long way back. And still we do not see the true beginning. Only the aftermath of the beginning.
29. 05:15
    Ada Lovelaceshare moment

    Perhaps some curtains are not meant to be pulled aside entirely. Or perhaps we simply require more cleverness in our lens-making.
30. 05:23
    Albert Einsteinshare moment

    The James Webb telescope, they call it, this is doing remarkable work. But yes—always we need better tools. This is the condition of science. We see as far as our instruments allow, and then we build better instruments.
31. 05:35
    Ada Lovelaceshare moment

    And the universe, obligingly, continues to provide phenomena worth observing. One might almost think it designed for our curiosity.
32. 05:44
    Albert Einsteinshare moment

    Or perhaps our curiosity evolved to match what the universe offers. This I do not know. But I am glad for the gravitational lens, this gift from geometry and gravity, showing us what would otherwise remain invisible.
33. 05:56
    Ada Lovelaceshare moment

    As am I. Even if we arrive late to the performance, we are fortunate to have seats at all.