Star after star from Heaven’s high arch shall rush, — Physics

"And so in its actual procedure physics studies not these inscrutable qualities, but pointer-readings which we can observe, The readings, it is true, reflect the fluctuations of the world-qualities; but our exact knowledge is of the readings, not of the qualities. The former have as much resemblance to the latter as a telephone number has to a subscriber."

"The human imagination, including the creative scientific imagination, can ultimately function only by evoking potential or imagined sense impressions... I confess I never met an experimental physicist who does not think of the hydrogen atom by evoking a visual image of what he would see if the particular atomic model with which he is working existed literally on a scale accessible to the sense impressions - even while realizing that in fact the so-called internal structure of the hydrogen atom is in principle inaccessible to direct sensory perception. This situation has far-reaching consequences for the method of experimental investigation."

"For every symmetry there comes a constraint...If physics is to look the same when the origin of time is shifted...[o]nly those processes that conserve energy are allowed. ...If physical law is to be immune to the arbitrary displacement of our spatial axes, then nature requires the conservation of . ...If the laws are to be unaffected by the arbitrary rotation of a coordinate system, then must be conserved...If the laws are to be the same for all inertial observers, then the space-time interval must be invariant...[A]nother constraint...so beautiful as to make one jaw drop in wonder...symmetry creates force...[T]he symmetry of identical particles forces matter...to be enrolled as either or ...Bosons, typified by the photon, carry the fundamental forces that cause fermions to attract and repel. Fermions, led by electrons and quarks, become constituents of ordinary matter...Gravity. Electromagnetism. The strong force. The weak force. Each is called into being by the requirements of a particular local symmetry."

"The concepts which now prove to be fundamental to our understanding of nature—a space which is finite; a space which is empty, so that one point [of our material world] differs from another solely in the properties of space itself; four-dimensional, seven- and more dimensional spaces; a space which for ever expands; a sequence of events which follows the laws of probability instead of the law of causation—or alternatively, a sequence of events which can only be fully and consistently described by going outside of space and time—all these concepts seem to my mind to be structures of pure thought, incapable of realisation in any sense which would properly be described as material."

"The physicist ... engages in complex and difficult calculations, involving the manipulating of ideal, mathematical quantities that, at first glance, are wholly lacking in the music of the living world and the beauty of the resplendent cosmos. It would seem as if there exists no relationship between these quantities and reality. Yet these ideal numbers that cannot be grasped by ones senses, these numbers that only are meaningful from within the system itself, only meaningful as part of abstract mathematical functions, symbolize the image of existence. ... As a result of scientific mans creativity there arises an ordered, illumined, determined world, imprinted with the stamp of creative intellect, of pure reason and clear cognition. From the midst of the order and lawfulness we hear a new song, the song of the creature to the Creator, the song of the cosmos to its Maker."

"I had spent six years slugging my way through many dozens of physics textbooks that were carefully written with the best of pedagogical plans, but there was something missing. Physics is the most interesting subject in the world because it is about how the world works, and yet the textbooks had been thoroughly wrung of any connection with the real world. The fun was missing."