Well, maybe not all scientists, but I just found an Archive of Scientists’ Transcendent Experiences.
While you’ll perhaps want to peruse several (or all?) of the testimonies, here’s a sample from Allan Smith’s “My Experience of Cosmic Consciousness”:
The Cosmic Consciousness experience began with some mild tingling in the perineal area, the region between the genitals and anus. The feeling was unusual, but was neither particularly pleasant nor unpleasant. After the initial few minutes, I either ceased to notice the tingling or did not remember it. I then noticed that the level of light in the room as well as that of the sky outside seemed to be increasing slowly. The light seemed to be coming from everywhere, not only from the waning sun. In fact, the sun itself did not give off a strong glare. The light gave the air a bright thickened quality that slightly obscured perception rather than sharpened it. It soon became extremely bright, but the light was not in the least unpleasant.
Along with the light came an alteration in mood. I began to feel very good, then still better, then elated. While this was happening, the passage of time seemed to become slower and slower. The brightness, mood-elevation, and time-slowing all progressed together. It is difficult to estimate the time period over which these changes occurred, since the sense of time was itself affected. However, there was a feeling of continuous change, rather than a discrete jump or jumps to a new state. Eventually, the sense of time passing stopped entirely. It is difficult to describe this feeling, but perhaps it would be better to say that there was no time, or no sense of time. Only the present moment existed. My elation proceeded to an ecstatic state, the intensity of which I had never even imagined could be possible. The white light around me merged with the reddish light of the sunset to become one all enveloping, intense undifferentiated light field. Perception of other things faded. Again, the changes seemed to be continuous.
At this point, I merged with the light and everything, including myself, became one unified whole. There was no separation between myself and the rest of the universe. In fact, to say that there was a universe, a self, or any ‘thing’ would be misleading — it would be an equally correct description to say that there was ‘nothing’ as to say that there was ‘everything’. To say that subject merged with object might be almost adequate as a description of the entrance into Cosmic Consciousness, but during Cosmic Consciousness there was neither ‘subject’ nor ‘object’. All words or discursive thinking had stopped and there was no sense of an ‘observer’ to comment or to categorize what was ‘happening’. In fact, there were no discrete events to ‘happen’ — just a timeless, unitary state of being.
Perhaps the most significant element of Cosmic Consciousness was the absolute knowingness that it involves. This knowingness is a deep understanding that occurs without words. I was certain that the universe was one whole and that it was benign and loving at its ground.
In terms of Buddhist teachings around meditative absorption, we’d say that Smith was blessed with a spontaneous tour through all four of the rupa (material) jhanas, at which point he seems to have hung out in the fourth for a while.
Yogis who maintain a serious daily meditation practice (i.e., at least three sessions a day, minimum of one hour each), who find time to do 10-day (or longer) retreats every year, become accustomed to “cosmic consciousness” as described here, finding that they are suffused and saturated in various levels of that state throughout each moment of the 24 hour cycle.
That scientists, who are accustomed to intense mental focusing, are reporting such experiences is, in my opinion, hopeful for life on planet Earth.
Good for Allan Smith, and may he revisit this state more and more frequently as his path deepens.