--- title: "Meaning & Key Takeaway of: The uncertainty relation does not refer…" description: "\"The uncertainty relation does not refer to the past; if the velocity of the electron is at first known and the position then exactly measured, the posi..." image: "https://sms4smile.com/quotes/i/b26/werner-heisenberg-4501_measurement_the-uncertainty-relation-does-not-refer_3007366.jpg" --- # The uncertainty relation does not refer to the past; if… ![“The uncertainty relation does not refer to the past; if the velocity of the electron is at first known and the position then exactly measured, the position for times previous to the measurement may be calculated.” quote by Werner Heisenberg](https://sms4smile.com/quotes/i/b26/werner-heisenberg-4501_measurement_the-uncertainty-relation-does-not-refer_3007366.jpg) [Download](https://sms4smile.com/quotes/i/b26/werner-heisenberg-4501_measurement_the-uncertainty-relation-does-not-refer_3007366.jpg) [Open image](https://sms4smile.com/quotes/i/b26/werner-heisenberg-4501_measurement_the-uncertainty-relation-does-not-refer_3007366.jpg) > “The uncertainty relation does not refer to the past; if the velocity of the electron is at first known and the position then exactly measured, the position for times previous to the measurement may be calculated.” [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) ## About This Quote This interpretation was drafted with AI assistance. It is one reading of the quote, not the author's own explanation. Quantum mechanics limits knowledge of past states when measuring present properties, not past events. **In simple terms:** Measuring now doesn’t change the past, but limits knowing it. Key Takeaway Accept uncertainty in past predictions. Themes physics uncertainty measurement Mood thoughtful analytical Type scientific philosophical When to use this quote - particle tracking - experimental design - historical data analysis Key Concepts quantum theory determinism observer effect Questions to Reflect On - How does measurement affect what we can infer about earlier states? - Can we ever fully know a particle’s history? A Different Perspective The principle assumes idealized conditions; real experiments add noise. ★ ★ ★ ★ ★ No ratings yet [Electron Known](https://sms4smile.com/quotes/about/electron-known-4804145/) [Measurement](https://sms4smile.com/quotes/about/measurement/) [Past](https://sms4smile.com/quotes/about/past/) [Past Velocity](https://sms4smile.com/quotes/about/past-velocity-4804146/) [Position](https://sms4smile.com/quotes/about/position/) [Theory](https://sms4smile.com/quotes/about/theory/) [Time](https://sms4smile.com/quotes/about/time/) [Uncertainty](https://sms4smile.com/quotes/about/uncertainty/) [Uncertainty Relation](https://sms4smile.com/quotes/about/uncertainty-relation-2963830/) [Velocity Electron](https://sms4smile.com/quotes/about/velocity-electron-4804147/) ## Related quotes > [“Heisenberg's uncertainty relation measures the amount by which the complementary descriptions of the electron, or other fundamental entities, overlap. 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Spaces between deaths.”](https://sms4smile.com/quotes/david-levithan/each-of-us-has-our-own-unit-of-measurement-our-own-relativity-spaces/) [David Levithan](https://sms4smile.com/quotes/author/david-levithan/) > [Golf is not, on the whole, a game for realists. By its exactitudes of measurements it invites the attention of perfectionists.](https://sms4smile.com/quotes/heywood-hale-broun/golf-is-not-on-the-whole-a-game-for-realists-by-its-exactitudes-of/) [Heywood Hale Broun](https://sms4smile.com/quotes/author/heywood-hale-broun/) > [True works of art contain their own theory and give us the measurement according to which we should judge them.](https://sms4smile.com/quotes/johann-wolfgang-von-goethe/true-works-of-art-contain-their-own-theory-and-give-us-the/) [Johann Wolfgang von Goethe](https://sms4smile.com/quotes/author/johann-wolfgang-von-goethe/) ## More by Werner Heisenberg > [“Revere those things beyond science which really matter and about which it is so difficult to speak.”](https://sms4smile.com/quotes/werner-heisenberg/revere-those-things-beyond-science-which-really-matter-and-about/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [“In the history of science, ever since the famous trial of Galileo, it has repeatedly been claimed that scientific truth cannot be reconciled with…](https://sms4smile.com/quotes/werner-heisenberg/in-the-history-of-science-ever-since-the-famous-trial-of-galileo-it/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [The more closely you look at one thing, the less closely can you see something else.](https://sms4smile.com/quotes/werner-heisenberg/the-more-closely-you-look-at-one-thing-the-less-closely-can-you-see/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [I think that if a United States of Europe were to be formed, it would be in our interests to fight for it, as…](https://sms4smile.com/quotes/werner-heisenberg/i-think-that-if-a-united-states-of-europe-were-to-be-formed-it-would/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [Whether we electrons, light quanta, benzol molecules, or stones, we shall always come up against these two characteristics, the corpuscular and the undular.](https://sms4smile.com/quotes/werner-heisenberg/whether-we-electrons-light-quanta-benzol-molecules-or-stones-we-shall/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [It is probably true quite generally that in the history of human thinking the most fruitful developments frequently take place at those points where…](https://sms4smile.com/quotes/werner-heisenberg/it-is-probably-true-quite-generally-that-in-the-history-of-human/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [If we made atomic bombs, we would bring about a terrible change in the world. Who knows what would happen from this?](https://sms4smile.com/quotes/werner-heisenberg/if-we-made-atomic-bombs-we-would-bring-about-a-terrible-change-in-the/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [The positivists have a simple solution: the world must be divided into that which we can say clearly and the rest, which we had…](https://sms4smile.com/quotes/werner-heisenberg/the-positivists-have-a-simple-solution-the-world-must-be-divided-into/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [“what we observe is not nature itself, but nature exposed to our method of questioning’.77”](https://sms4smile.com/quotes/werner-heisenberg/what-we-observe-is-not-nature-itself-but-nature-exposed-to-our-method/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [A consistent pursuit of classical physics forces a transformation in the very heart of that physics.](https://sms4smile.com/quotes/werner-heisenberg/a-consistent-pursuit-of-classical-physics-forces-a-transformation-in/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [ It was about three o'clock at night when the final result of the calculation \[which gave birth to quantum mechanics\] lay before me ...… ](https://sms4smile.com/quotes/werner-heisenberg/it-was-about-three-o-clock-at-night-when-the-final-result-of-the/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [Only a few know, how much one must know to know how little one knows.](https://sms4smile.com/quotes/werner-heisenberg/only-a-few-know-how-much-one-must-know-to-know-how-little-one-knows/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [“We have to remember that what we observe is not nature in itself but nature exposed to our method of questioning. ”](https://sms4smile.com/quotes/werner-heisenberg/we-have-to-remember-that-what-we-observe-is-not-nature-in-itself-but/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [I think that modern physics has definitely decided in favor of Plato. In fact the smallest units of matter are not physical objects in…](https://sms4smile.com/quotes/werner-heisenberg/i-think-that-modern-physics-has-definitely-decided-in-favor-of-plato/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) > [The end of the First World War had thrown Germany's youth into great turmoil. The reins of power had fallen from the hands of…](https://sms4smile.com/quotes/werner-heisenberg/the-end-of-the-first-world-war-had-thrown-germany-s-youth-into-great/) [Werner Heisenberg](https://sms4smile.com/quotes/author/werner-heisenberg/) [Explore all 109 Werner Heisenberg quotes ](https://sms4smile.com/quotes/author/werner-heisenberg/) ## More Measurement quotes > [True works of art contain their own theory and give us the measurement according to which we should judge them.](https://sms4smile.com/quotes/johann-wolfgang-von-goethe/true-works-of-art-contain-their-own-theory-and-give-us-the/) [Johann Wolfgang von Goethe](https://sms4smile.com/quotes/author/johann-wolfgang-von-goethe/) > [Golf is not, on the whole, a game for realists. By its exactitudes of measurements it invites the attention of perfectionists.](https://sms4smile.com/quotes/heywood-hale-broun/golf-is-not-on-the-whole-a-game-for-realists-by-its-exactitudes-of/) [Heywood Hale Broun](https://sms4smile.com/quotes/author/heywood-hale-broun/) > [“Each of us has our own unit of measurement, our own relativity. Spaces between loves. Spaces between destinations. Spaces between deaths.”](https://sms4smile.com/quotes/david-levithan/each-of-us-has-our-own-unit-of-measurement-our-own-relativity-spaces/) [David Levithan](https://sms4smile.com/quotes/author/david-levithan/) > [All 50 states had the same national economy. And on virtually any measurement you wish to look at, Michigan has moved up and improved…](https://sms4smile.com/quotes/john-engler/all-50-states-had-the-same-national-economy-and-on-virtually-any/) [John Engler](https://sms4smile.com/quotes/author/john-engler/) > [“The measure of who you are will always exceed measurement.”](https://sms4smile.com/quotes/craig-d-lounsbrough/the-measure-of-who-you-are-will-always-exceed-measurement/) [Craig D. Lounsbrough](https://sms4smile.com/quotes/author/craig-d-lounsbrough/) > [Cookery is not chemistry. It is an art. It requires instinct and taste rather than exact measurements.](https://sms4smile.com/quotes/marcel-boulestin/cookery-is-not-chemistry-it-is-an-art-it-requires-instinct-and-taste/) [Marcel Boulestin](https://sms4smile.com/quotes/author/marcel-boulestin/) > [There was but one question he left unasked, and it vibrated between his lines: if gross miscalculations of a person's value could occur on…](https://sms4smile.com/quotes/michael-lewis/there-was-but-one-question-he-left-unasked-and-it-vibrated-between/) [Michael Lewis](https://sms4smile.com/quotes/author/michael-lewis/) > [Measurement of life should be proportioned rather to the intensity of the experience than to its actual length.](https://sms4smile.com/quotes/thomas-hardy/measurement-of-life-should-be-proportioned-rather-to-the-intensity-of/) [Thomas Hardy](https://sms4smile.com/quotes/author/thomas-hardy/) > [Learning is the measurement of knowledge before and after.](https://sms4smile.com/quotes/eben-pagan/learning-is-the-measurement-of-knowledge-before-and-after/) [Eben Pagan](https://sms4smile.com/quotes/author/eben-pagan/) > [It is much easier to make measurements than to know exactly what you are measuring](https://sms4smile.com/quotes/j-w-n-sullivan/it-is-much-easier-to-make-measurements-than-to-know-exactly-what-you/) [J. W. N. Sullivan](https://sms4smile.com/quotes/author/j-w-n-sullivan/) > [Man up and add a tux to your wardrobe. Just find one you like and get it well-tailored to your own measurements.](https://sms4smile.com/quotes/paul-feig/man-up-and-add-a-tux-to-your-wardrobe-just-find-one-you-like-and-get/) [Paul Feig](https://sms4smile.com/quotes/author/paul-feig/) > [While love is common, true love is rare, and I believe that few people are fortunate enough to experience it. The roads of regular…](https://sms4smile.com/quotes/david-buss/while-love-is-common-true-love-is-rare-and-i-believe-that-few-people/) [David Buss](https://sms4smile.com/quotes/author/david-buss/) > [As regards the quietude of the sage, he is not quiet because quietness is said to be good. 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I'm trying to be more open to vulnerability and mistakes.](https://sms4smile.com/quotes/micah-lexier/as-i-m-getting-older-i-m-moving-away-from-calculations-and/) [Micah Lexier](https://sms4smile.com/quotes/author/micah-lexier/) [Browse all 362 Measurement quotes ](https://sms4smile.com/quotes/about/measurement/) ```json { "@context": "https://schema.org", "@graph": [ { "@type": "Quotation", "text": "The uncertainty relation does not refer to the past; if the velocity of the electron is at first known and the position then exactly measured, the position for times previous to the measurement may be calculated.", "creator": { "@type": "Person", "name": "Werner Heisenberg" }, "isPartOf": { "@id": "https://sms4smile.com/quotes/#website" }, "url": "https://sms4smile.com/quotes/werner-heisenberg/the-uncertainty-relation-does-not-refer-to-the-past-if-the-velocity/", "about": { "@type": "Thing", "name": "Measurement" }, "@id": "https://sms4smile.com/quotes/werner-heisenberg/the-uncertainty-relation-does-not-refer-to-the-past-if-the-velocity/#quotation", "image": { "@type": "ImageObject", "@id": "https://sms4smile.com/quotes/i/b26/werner-heisenberg-4501_measurement_the-uncertainty-relation-does-not-refer_3007366.jpg", "contentUrl": "https://sms4smile.com/quotes/i/b26/werner-heisenberg-4501_measurement_the-uncertainty-relation-does-not-refer_3007366.jpg", "url": "https://sms4smile.com/quotes/i/b26/werner-heisenberg-4501_measurement_the-uncertainty-relation-does-not-refer_3007366.jpg", "width": 1080, "height": 1080, "caption": "“The uncertainty relation does not refer to the past; if the velocity of the electron is at first known and…” — Werner Heisenberg", "creditText": "SMS4Smile Quotes", "creator": { "@id": "https://sms4smile.com/quotes/#organization" } } }, { "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://sms4smile.com/" }, { "@type": "ListItem", "position": 2, "name": "Quotes", "item": "https://sms4smile.com/quotes/" }, { "@type": "ListItem", "position": 3, "name": "Werner Heisenberg", "item": "https://sms4smile.com/quotes/author/werner-heisenberg/" }, { "@type": "ListItem", "position": 4, "name": "The uncertainty relation does not refer...", "item": "https://sms4smile.com/quotes/werner-heisenberg/the-uncertainty-relation-does-not-refer-to-the-past-if-the-velocity/" } ], "@id": "https://sms4smile.com/quotes/werner-heisenberg/the-uncertainty-relation-does-not-refer-to-the-past-if-the-velocity/#breadcrumb" }, { "@type": "WebSite", "@id": "https://sms4smile.com/quotes/#website", "name": "SMS4Smile Quotes", "url": "https://sms4smile.com/quotes/", "publisher": { "@id": "https://sms4smile.com/quotes/#organization" } }, { "@type": "Organization", "@id": "https://sms4smile.com/quotes/#organization", "name": "SMS4Smile Quotes", "url": "https://sms4smile.com/quotes/", "logo": { "@type": "ImageObject", "url": "https://sms4smile.com/quotes/wp-content/themes/sq/assets/icons/icon-512.png", "width": 512, "height": 512 } } ] } ```