It is interesting to consider how a given day, otherwise completely ordinary in every respect, may be given tremendous import by the actions or words of a single man.  This man may be any sort of man, and his action may be any sort of action, but the rippling, ever-spreading chains of consequence that he initiates can make the most impossible events occur - given sufficient time.  

This is what Dr. Khross thought as he stood at the lectern, using the last few moments before his presentation to reflect on the untold sequences of consequence and coincidence that had brought him here before the Academy of Quantum Sciences to explain his newly-completed project.  Then the cue light flashed, the lights dimmed, and the lecture-hall murmur died out as his audience directed their attention toward him and his work.  He cleared his throat, and began.

"My fellow Mechanicians, I thank you all for being here today.  I will try to be brief; I realize our time is valuable - may, in fact, realize it better than anyone present today - so I will ask you to please hold your questions until the end of the presentation.  Thank you."

"The device I have brought before you today is known as the Quantum Field Arrestor.  It is based on the principles of Sephil-Severides quantum field analysis, a field that you are no doubt familiar with" - here a quiet chuckle arose from the audience, as many had spent their whole lives applying the theories of the founding Mechanicians - "and which I will therefore not reiterate at this point.  It will suffice for me to say that I have discovered a heretofore unexplored application of their quantum field equations which suggests a method by which the vibrations of the quantum field may be halted and restarted at will."

A collective gasp rose from the audience, and several amazed outbursts reached Khross' ear as he waited patiently for the crowd to settle back into their seats.  He saw Dr. Tanaka yank her colleague Henson into the aisle and out through the back exit; her career had been staked on proving that what Khross had just suggested was, in fact, impossible.  She was by no means alone in this pursuit, and Khross noted some others as they made a less hasty move toward the doors.  He saw Jansson go looking as though he were about to weep; Jansson had just last week submitted his magnum opus to the Academy for peer review.  It was a set of proofs that he believed would settle the question of quantum field cessation; it had cost him his marriage, and would have been the keystone of his career.  If Khross were right, it would invalidate his work at a stroke; Jansson would no doubt be doing some serious soul-searching in the next few weeks.

Khross considered this all with a certain professional detachment; his work would ruin more than those two careers, but he couldn't reproach himself for having found the truth first.  He was not an imposing man, but he had the strength of self-certainty, and perhaps the greatest analytical mind in the Academy, an organization known for attracting the best minds from all over the Settled Worlds.  With these assets, he watched as his audience calmed down; though somewhat thinned, the crowd that remained was clearly intrigued by his statement, and he continued.

"As I was saying, I have discovered a method by which the quantum field may be stopped or started at will.  If you will please direct your attention toward the main display, I will give a brief explanation of this method..." A slew of symbols appeared in the space behind Khross, and he gestured towards each in turn as he explained his findings.  As one brilliant intuition followed another, his audience grew more an more rapt, until Khross once more turned to face them - "... and having established the field polarity reversal, we can maintain it for an indefinite period of time, thus creating an effectively permanent zero-entropy system."  He paused to let this sink in.  "While under the influence of this field polarity reversal, an observer would have no concept of time, or indeed, perception of any activity at all.  The longest duration imaginable would be as a single moment to him.  I see that some of you have seen where my discussion is headed, so I will cut directly to my point:  it is my belief that the Quantum Field Arrestor is, in effect, a practical time-machine."

There was an immediate fervor as Khross pronounced the words "time-machine."  The undercurrent of violence was more pronounced at this point, as nearly all the assembled Mechanicians had assumed that such a device was impossible; meeting no resistance to their assumption had hardened it as the years went by, to the point that Khross' conclusion was, in effect, scientific heresy.  He raised a placatory hand, and slowly the audience calmed once more.  Khross continued.

"I apologize for choosing this setting to challenge one of the dogmatic principles of our society, but I did not wish to have my research interfered with.  Please forgive my indiscretion; as a token of my remorse, I hope you will allow me to dedicate the first test of this device to you, the members of the Academy.  This will be in a few moments, but I would like to explain a bit about the functionality of the device before I demonstrate it."  Khross dipped below the lectern for a moment, and came back up holding a silver object roughly the size of a briefcase.  It was a dull lustrous grey, and had on the large face a panel with several dials and buttons.

"The device itself is capable of travel in only one direction - to the future.  However, since it is effectively everlasting, unbelievably vast stretches of time may be crossed at a bound.  Such time may be crossed as to comfortably allow for the birth and death of several hundred billion universes, if necessary.  The subject engaging in the travel perceives nothing during this time lapse.  The end point is determined by quantum field analysis of the present surroundings combined with a quantum field offset corresponding to the amount of time one wishes to offset from the present.  Thus, if one wanted to travel into a past corresponding to a year prior to the present date and setting, the device would analyze the present field, use this to determine the quantum field state at the desired time, and then begin emitting the reverse-polarized field to the required diameter.  Within this diameter, the quantum field will be static; reanimation of the field is achieved by the presence of the field corresponding to the desired end point.  At this point, I will demonstrate the device, projecting myself fifteen minutes into our present future.  No long bounds of time will be needed, but I believe the demonstration will be effective all the same.  Please remain clear of the stage."  Khross then fiddled with a knob or two on the surface of the device, pressed a button, and - disappeared.

The effect on the audience was electrifying.  It was as though they had seen magic done before their eyes, only they knew this was no trick.  Several of the more intrepid Mechanicians advanced cautiously on the stage, pulling field analyzers from their pockets and brandishing them like spears before the void where Khross had vanished.  Every one had a reading of Zero - no field detected, a response thought to be impossible.  As the fifteen minute mark approached, the Mechanicians retreated to their seats.  Khross reappeared on schedule, stepped back to the lectern, and addressed his audience once more.

"Thank you for being so patient.  This concludes my presentation.  Are there any questions?"