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Introduction toModern PhysicsWelcome toPhy 33055th Solvay Conference on electrons and photons17 Nobel prize winners in the photoPhysics 3305 - Modern PhysicsProfessor Jodi Cooley

SMU Honors Physics (PHYS 1010)Prof. Stephen Sekula Christopher MilkeLet us take a trip to an alien worldFirst Meeting: Aug. 22, 6:15pm, FOSC 60Free Food!PHYS 1010 www.physics.smu.edu/sekula/honors Zero-credit-hour add-on to introductoryphysics sequenceMeets once per week (6:15pm – 7:30pm)1 team-based semester-long projectEarn “Honors” designation on transcriptLearn physics by subject immersionPhysics 3305 - Modern PhysicsProfessor Jodi Cooley

AnNouncements- Reading Assignments:Chapter 1 (all) and Chapter 2.1 - 2.3- First homework assignment was given out today and isdue Tuesday, August 29th.- Read the homework policy!- Read the syllabus!- Read the hand out on sig figs!Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Course InstructorProfessor Jodi CooleyOffice: 151 Fondren [email protected] James [email protected] 3305 - Modern PhysicsProfessor Jodi Cooley

Course InstructorProfessor Jodi CooleyOffice: 151 Fondren [email protected]: Tues & Thurs. 12:30 - 1:50 pmOffice Hours:TBDFill out doodle poll by NOON on Wednesday (Aug. 22).http://doodle.com/poll/72sm895av3wk2gpnPhysics 3305 - Modern PhysicsProfessor Jodi Cooley

NOTE: This course does not use blackboard.Course extBoOkModern Physics by Randy Harris (2nd Edition)I also recommend that you consider purchasing amathematical handbook (i.e. Schaum’s Outline Series:Mathematical Handbook of Formulas and Tables byMurray R. Spiegel, 3rd. edition)Extra Credit - SeE HandoutFree one-year membership to APS gives subscription to Physics ysics 3305 - Modern PhysicsProfessor Jodi Cooley

Surgeon General’s Warninga)Too much exposure to Modern Physics may cause severe headaches,. ok not true, but: You have ALL been learning and doing classical physics for about 20 years NONE of you have had any first hand experience with modern physics Will be introduced to some counter-intuitive concepts Do not expect to be able to do the problems on the very first try. Giveit 3-4 legitimate tries before seeking help. Collaborating with classmates on solving problems is acceptable (in fact, itis encouraged!), but the solutions you hand in MUST be your own (see SMUHonor Code) No credit for late homework. Attendance: Judge for your self, . how many SMU courses were you ableto master by just staying at home and reading the book Corollary: Don’t expect to be able to brush off the course for a wholesemester and learn everything by cramming for a whole day prior to theexam, it also doesn’t work to eat burgers all semester expect to lose 10 lbsby going to the gym for 24 hrs straight?Physics 3305 - Modern PhysicsProfessor Jodi Cooley

How to Do WelLin the coursea)Do all the homework sets!b)Study in small groups (make sureyou’re contributing to the group asmuch as your absorbing from it)c)Come to classd)Don’t waste time on last minuteall-nightersPhysics 3305 - Modern PhysicsYour Grade:15% Homework5% Quizzes40% Midterm exams20 % Presentation20 % Final ExamProfessor Jodi Cooley

How to Do WelLin the courseEveryone has a chance to earn an Ain this class. There is no s 3305 - Modern PhysicsAAB BBC CC-Your Grade:15% Homework5% Quizzes40% Midterm exams20 % Presentation20 % Final ExamProfessor Jodi Cooley

ExpectationsWhat to expect from me An interesting and thoughtprovoking course Consideration and fairness(this does not mean easy!) Availability & approachabilityto talk to about anydifficulties & questionsWhat I expect from you Sincere effort Honesty Homework should follow thehomework guidelines on thecourse website. Punctuality PunctualityPhysics 3305 - Modern PhysicsProfessor Jodi Cooley

TopicsSpecial Relativity(ch 2)Atomic Physics & Spin(ch 8)The Nature of Particles(ch 3 - 4 )Statistical Physics *(ch 9)Quantum Mechanics(5 - 7)Other Topics(student presentations)* Time permittingPhysics 3305 - Modern PhysicsProfessor Jodi Cooley

What is Plagiarism?Physics 3305 - Modern PhysicsProfessor Jodi Cooley

entHandbook/HonorCodePLAGIARISM5 Intentionally or knowinglyrepresenting the words or ideas of another as one’sown in any academic exercise.5 In regards to cases of plagiarism, ignorance of therules is not an excuse. The University subscribes to thestatement on plagiarism which appears on page six ofWilliam Watt’s An American Rhetoric (1955).SPhysics 3305 - Modern PhysicsProfessor Jodi Cooley

Plagiarisma)It is plagiarism to copy your homework from theInstructor Solution Manuel.b)It is plagiarism to copy the homework from anotherstudent (current or previous).c)It is plagiarism to copy the solutions to yourhomework from google.d)Academic honesty means that you acknowledge yoursources! This includes people in your study group.I will report future incidents of plagiarism to the HonorCouncil. If you have any questions about academic honesty inthis class, please feel free to talk to me during office hours.Physics 3305 - Modern PhysicsProfessor Jodi Cooley

ThE Constitution of theHonor Council of SmUPREAMBLE AND DEFINITIONS We, the students of Southern Methodist University,with the approval of the Provost and the Dean of Student Life, establish the HonorCouncil to uphold the standards of academic integrity set forth in the Honor Code. Actspunishable under the code include, but are not limited to the following:ACADEMIC SABOTAGE Intentionally taking any action which negatively affects theacademic work of another student.CHEATING Intentionally1 using or attempting to use unauthorized materials,information, or study aids in any academic exercise2.FABRICATION Intentional and unauthorized falsification or invention of anyinformation or citation in an academic exercise3.FACILITATING ACADEMIC DISHONESTY Intentionally or knowingly helping orattempting to help another to violate any provision of the Honor Code4.PLAGIARISM5 Intentionally or knowingly representing the words or ideas of another asone’s own in any academic exercise.Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Student ConductPhysics 3305 - Modern PhysicsProfessor Jodi Cooley

Details**In general you can expect the following schedule for assignments.However, you must pay attention as exam weeks and weeks whenthere are vacation days, assignment due dates may change.Tuesdays: Homework is due. Homework is assignedfor the following week. Regrade requests aredue from assignmenthanded back onprevious Thursday.Physics 3305 - Modern PhysicsThursdays: Graded homework isreturned. Regraded homework isreturned.Note: In order for a problem to qualify fora regrade, you must have made an honestattempt of the problem on the originalproblem. Abuse of the regrade system willresult in *NO* regrades for the entire class.Professor Jodi Cooley

file:///Users/cooley/Downloads/PHYS3305 OpeningCredits.medium.webmPhysics 3305 - Modern PhysicsProfessor Jodi Cooley

Newtonian PhysicsDeveloped in the 1800’s, extended forward 200 years. Force andacceleration are related to each other through inertial mass.-Kepler’s laws (accurate for many objects)-Mass was recognized as a body’s tendency to resist changesin motion (inertia).-Light identified as a wave phenomenon.Energy is a fundamental quantity that can not be created ordestroyed, only transferred.Electricity and magnetism were revealed as two faces of thesame underlying phenomenon - Electromagnetism. Allelectric and magnetic phenomenon could be described aswaves.Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Newtonian physicsa)This view of the universe suggested that space and timeare the same for all observers, regardless of their stateof motion.b)Energy is different from mass and both came incontinuous units.c)All things could be predicted.-Light was identified as alternating electric and magneticwaves traveling at c 2.995 x 108 m/s. It was assumedthat light (as all EM waves) propagated in medium (theether) and was affected by the motion of that substance.Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Failures of ClasSical Concepts Pions are created in high energycollisions of two protons. Theyeventually decay to muons. Situation (a): Physics 3305 - Modern PhysicsPions producedat rest in the laboratory areobserved to have an averagelifetime of 26.0 ns. (observer 1)Situation (b): Pions moving at2.737 x 108 m/s (0.913 c) havean observed lifetime of63.7 ns. (observer 2)Professor Jodi Cooley

Failures of ClasSical Concepts- Pions are created in high energycollisions of two protons. Theyeventually decay to muons.- Situation (a):Pions producedat rest in the laboratory areAccording to Newton’s Laws, time is the same for allobserved to have an averageobservers. This experimentdemonstratesthatthislifetime of 26.0 ns. (observer 1)assumption is not true!- Situation (b):Pions moving at2.737 x 108 m/s (0.913 c) havean observed lifetime of63.7 ns. (observer 2)Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Failures of ClasSical Concepts Pions are created in high energycollisions of two protons. Theyeventually decay to muons. Situation (a): Distancebetween the two markers ismD1 (2.737 10)(63.7 10s8 s) 17.4 mSituation (b): Distancebetween the markers ismD1 (2.737 10)(26.0 10s8Physics 3305 - Modern Physics99s) 7.11 mProfessor Jodi Cooley

Failures of ClasSical Concepts Pions are created in high energycollisions of two protons. Theyeventually decay to muons. Situation (a): Distancethe two ismarkersisAccording to Newton’sbetweenLaws, distancethe samefor all observers. Againwefind8 m that thisD1 (2.737 10)(63.7 10 9 s) 17.4 msassumption is not true! Situation (b): Distancebetween the markers ismD1 (2.737 10)(26.0 10s8Physics 3305 - Modern Physics9s) 7.11 mProfessor Jodi Cooley

Failures of Newtonian physicsa) Michelson and Morley Experiments: Light was unaffected bythe motion of the observer. (Next class period).b)The laws of E&M appeared ‘special’ in that their form changeddepending on the state of motion of the observer (hwk 4c).c) Theory of heat failed to predict the energy emitted by ablackbody. (Chapter 3)- Heat is the thermal motion of atoms in a body.Consider heattrapped in a cavity (blackbody). The emitted spectrum ofenergy becomes infinite as the energy of radiation increases.This would cause the destruction of the universe if even oneblackbody were in existence.- Measured spectrums of real blackbodies show an increase andthen cut-off.Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Modern Physicsa)Two Basic Ideas:-Time and space are not absolutes.Particles behave like waves and waves behave likeparticles.b)Two Branches:-Special RelativityQuantum Mechanicsc)With an understanding of these branches, we can thenexplore areas of modern physics such as superconductivity,modern optics, nuclear physics, particle physics andcosmology - along with a host of other areas of science.Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Physics 3305 - Modern PhysicsProfessor Jodi Cooley

SpeEd of lightwalking 1 m/srunning 2-3 m/sdriving 25 m/s (highway)flying 225 m/ssound 300 m/snavigational satellite 1000 m/slight 3 x 108 m/sPhysics 3305 - Modern PhysicsProfessor Jodi Cooley

Synchronizing a SymphonyA conductor is not just part of the social construct ofan orchestra. He is required by the speed of sound andspeed of light.The distance between our ears is 22 cm. The humanauditory system is capable of discerning sounds thatare no more than 0.660 ms apart (Duplex theory). Thismeans that sounds arriving within 0.660 ms of eachother sound as if they arrive at the same time.Orchestra decides to toss the conductor.Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Synchronizing a SymphonyDoes it make a difference?Say, oboe at the center of the orchestra keeps thetempo.How long does it take to reach the players at the edge ofthe pit which is 10 meters away?10 m 300 m/s 0.033 s or 33 msPlayers at the edgeare 33 ms late.Since the human ear is capable of discerning thedifference in sounds that are 0.66 ms apart, this is aproblem. The whole orchestra will be out of sync.Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Synchronizing a SymphonyWhy does the conductor fix this problem?The conductor uses light, not sound, to synchronize8the orchestra. Light travels at 3 x 10 m/s whichmeans that it takes only 0.000067 ms for the playersat the back of the pit to see the hand gesture.Hence, they are only 0.000067 ms out of sync withthe players from the front of the orchestra.The human ear is only able to discern a difference of0.66 ms in sounds. So, the orchestra sounds in sync.Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Thunder and LighteningThunder and lightening during in a storm are generatedat the same time. Assume that the distance between youand the source is d. Calculate the difference in time youobserve between the lightening and thunder.dtl cdandts vs1ddd d( )ts tl vscvsc11 )ts tl d(300 300, 000, 000d[s]ts tl 300Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Next Time:Michelson - Morley: The downfall of the ether!Simultaneity: Will two observers always agreethat two events are simultaneous?Physics 3305 - Modern PhysicsProfessor Jodi Cooley

The End(for today)Physics 3305 - Modern PhysicsProfessor Jodi Cooley

Welcome backto PHY 3305Today’s Lecture:General RelativityAlbert Einstein1879-1955Physics 3305 - Modern PhysicsProfessor Jodi Cooley

AnNouncements-There will be no lecture video (and hence no quiz) on Tuesday,September 13th. We will be do