voko said:
Call it whatever you want. Note that you are doing this, by saying something about what would happen if t.transistors could not exist; I merely say that we do not really know.
Ahhg,

<frustrated>. I am not saying "what
would happen" if transistors could not exist, or what would have happened if transistors were not invented circa 1947.
What I am stating, quite matter of factly even, what would
not happen without transistors, today, with today's technology (for reasons of practicality, cost, size, power consumption, material resources, etc.): You would not be reading this thread. You would not have access to a computer that could fit in your lap or a smartphone that could fit in your pocket.
Look what you just did. You are saying that now, in 2014, suddenly without transistors, building that behemoth would be my only option.
Yes, that is more like it. That is what I am saying. :)
Let me remind you that such a behemoth would have been the outcome if somebody had tried to achieve the same goal in 1947, using the technology available.
It would still require a behemoth but could be reduced to merely a fraction of the size of what it would otherwise be by replacing the vacuum tubes and electromechanical relays with discretely packaged transistors. (Still a behemoth, but a much smaller behemoth than what would otherwise be required.) This actually was the course of technological advancement in our history, although no one ever attempted to build anything equivalent to the computing power of a modern day smartphone with 1940's technology. What
did happen (in addition to computers becoming smaller behemoths) is discretely packaged transistors almost instantaneously changed radios from being pieces of furniture to something that you could hold in your hand and carry around with you.
Since the transistor's invention, engineers, physicists and scientists have been struggling to improve upon the idea. This started by shrinking the transistor size, putting more transistors on the same substrate (integrated circuits), and repeating.
In 1965, Gordon E. Moore published a paper describing a trend: the number of transistors that can fit on a given area of substrate had increased exponentially with time, given the continuous advancements in transistor technology. This eventually became known as "Moore's law." Although the exponential time constant was modified, the exponential quality continued for decades.
But engineers and physicists knew that Moore's law must eventually come to an end. As soon as transistor size hits "the wall" of quantum mechanical limitations, transistor size will shrink no further, at least not without a serious paradigm shift. Engineers and physicists have been searching for such a paradigm shift for decades, in anticipation of Moore's law failure. Today, we are already at the point of diminishing returns. Effort has been put on better utilization of the third dimension (taller gates, stacking transistors on top of one another, etc.) with some limited success, but nothing that will keep Moore's law going as it once was. Better lithography techniques have been accomplished in part by using light sources with higher frequency (makes me think of blue LEDs for some reason), and clever use of optics (liquid lenses for example). [All good stuff, but not enough to maintain Moore's law more than a handful of years or so.]
Before moving on, let me state this clearly: This "wall" seems much, much larger for the technology of vacuum tubes and electromechanical relays. Given what we know today, one cannot squeeze hundreds of millions of electromechanical switches and/or vacuum tubes (and have them work correctly) onto an area the size of your fingernail, and at a manufacturing cost of a few dollars. This version of Moore's law would plateau at the behemoth level.
The paradigm shift of replacing the transistor altogether has not been ignored, however. Quite the contrary. Effort has been made and studies done to explore such things such as purely optical, non-transistor switches; [and separately] properties of carbon nanotubes, to name a couple of examples. Nothing has panned out just yet. But don't think that engineers and physicists have been sitting idly by, twiddling their thumbs this whole time, complacent with the transistor. They have not. Possible alternatives to the transistor have been explored for decades. Maybe with continued research and increased technological advancement, we might move from the transistor to something else one day.
Modern day engineers and physicists have one advantage that scientists circa 1947 did not: transistor based tools, such as computers, and transistor based laboratory instrumentation (something that you can fit on a lab bench rather than filling up an entire building).
60 years of technological advance is something that you consistently ignore in your conjectures.
I am ignoring it because that is speculating about alternative timelines. I don't know what would have happened in the last 60 years if the transistor had not been invented any more than what would have happened if the Nazis had won World War II. Physics Forums is not the place for such speculations.
What I do know is that engineers and physicists have been searching for a transistor replacement for decades, utilizing incredible tools such as the transistor based computer to aid the effort. They have not found a feasible replacement for the transistor just yet, although they keep trying. (Maybe one day). So the real question is: Do you honestly think that taking away their incredible tools would
help that effort?