Physics 494, Autumn 2015
Senior Seminar: Current Problems in Physics



Giving a talk is a skill that will be useful in any type of career. Fortunately, how to give a good talk is a skill that can be learned and this is part of why you are taking this class.

The following contains a recipe and few simple guidelines that should be applicable to most type of talks you will be giving

In this class the talks for Phys494 are 15 minutes long followed by a 5 minute question section at the end.  


Select concepts/key points you want the audience to get

First, make a list of a few (three or less) most important and interesting key points you really want to convey to the audience. For example, in a talk for physicists, these central points may include the nature and purpose of a single device, the general idea, key result and implications of one experiment, or the highlights and consequences of one particular discovery or idea, etc. Fewer than three points is better for a short talk.  Around these points you will build your PowerPoint (or similar) deck.


Building the talk around the selected concepts/key points

1. Introduction: (~3 min) Explain the big picture and build the background so that your central point(s) are put into context. State the goals or purpose of your project/research. Set up your key point in the introduction to your talk.

2. Body: (~10 min) Explain your key points in the body of your talk. Here's where you use most of your slides. In the body of your talk, you take your audience (in steps that flow together logically) from their state of knowledge before your talk to an understanding of your key points.

3. Conclusion/Summary: (~2 min) Recap your key points at the end of your talk. (Repetition is a fundamental concept of learning.)

To spice up your conclusion you may want to leave your audience with a provocative question or bit of information beyond what you've already told them.


You may find it helpful to develop the talk from the inside out: write the talk’s body first, then the conclusion, and last the introduction.


Preparing the PowerPoint slides.

·         Most importantly your talk must be clear and understandable. Taylor the talk to the audience: consider the audience’s background and their interests. People like what they understand.

·         Make slides in landscape aspect ratio.

·         Try to use the same layout, background (and logo) on all slides. No background (i.e. white)  and no logo is fine.

·         The first slide should just contain the title of your talk, your name (and the name of collaborators) and your association (e.g. University of Washington or so). You can also put a catchy picture that has something to do with the talk on the slide. This slide will be up when you get introduced. If no one introduces you then you would have to read it off. (I will introduce you.)

·         A PowerPoint slide that has just about the right information content takes about 1.5 minutes per slide.

·         Every slide should have a headline explaining what is on the slide. The last slide’s headline invariably is the Summary or Conclusion.

·         Keep slides simple, Transparencies should not contain anything other than what you want your audience to pay attention to.

·         Slides must be readable. The oldest person in the back of the room must be able to read every word. àUse 28pt or larger characters. The best character type is Arial.

·         Use simple PowerPoint animation if you want to build up a point one a slide.

·         Do not try to impress the audience with complicated words (in the slides and in your speech)

·         Simple text and sentence structure is most effective.

·         Slides should contain no long text. Bullet points are effective. Bullets should be one-line statements; long sentences are very undesirable.

·         Use color (never more than 3 different text colors), bold style, underline to emphasize

·         Use either a white or a black background. Generally a black background is good, but most figures/graphs that you find are on a white background; these figures will be very bright and text near will be hard to see.

·         Do not overload the audience with information. Omit technical details.

·         Figures and pictures convey more information than textà most of the area on each slide should be figures/pictures/graphs. Make sure all figures have good resolution.

·         On graphs, make sure the axis are labeled and have units. If the labels are too small use PowerPoint to paste bigger labels over the too small ones. Make sure the graph is big enough. This gives the listener more time to understand the graph. At the bottom of a slide with a graph you should list the take-home message preferably in one sentence.

·         Use movies only if they are short and necessary.

·         If possible avoid complicated equations. Never more than one simple equation on a slide. Explain what the symbols in the equation are. Never show a derivation. Emphasize concepts and results, not details and mathematics.

·         Cite important papers at the bottom of your slide. Its best to just keep the first author’s name (e.g. Smith et al, Nature, (2015))  

·         Rule of thumb: no slide should contain more than 10 separate items of information.

·         Never put anything on a transparency that you will not talk about.


How to give the talk:

·         Practice, practice, practice.... makes perfect.

·         You can give the first few practice talks to yourself. It is important that you speak the words out loudly and not just run the talk in your head. (There are neurons in your brain that will have to connect to the speech center in your head to where the information of your talk is stored) àThe more often you practice a talk the more efficient you will be at selecting the words.

·         Repeat words that are difficult for you to pronounce 20 times or more (to yourself)

·         Practice in front of a mirror or record a video of your presentation.

·         Give a practice talk to another person(s). That person should time you and should be nice enough to give you honest feedback. Run through the entire talk with no interruptions, while your friend scribbles down notes. Turn on page numbers in your PowerPoint deck so your friend can critique every slide. Then sit down with your friend and go through every slide.

·         When you give a talk in front of a big audience it may run 10-20% faster because of the adrenaline that you will have flowing. (Adrenaline makes most people think faster.)

·         If your talk is still too long you must remove some content


Technical issues you have to clear up before you give the presentation:

·         Have a good pointer ready and know how to operate it (we’ll have one in class). Green laser pointers are better than red laser pointers. An old fashioned pointer (stick) is often most effective and does not run out of battery. If the screen is nearby, walk up to the screen and point at it with your hand. This makes for a more engaging talk. (Laser pointers amplify shaking of your hand and show that you are nervous)

·         Test automatic slide advance clickers, if possible practice with them.

·         Know how to operate the computer you are giving the presentation with. Know how to make the computer display slides in presentation mode. Turn off your laptop's screen saver, turn off Skype, messaging, or other software that may produce pop ups.

·         If the computer is not your own computer, test in advance that it can display your flavor of PowerPoint (fonts may be different, movie drivers may not be installed, etc.).

·         If you use your own computer make sure you have the proper adapter. To date, the VGA-D-connector is most common input. You should bring the appropriate adapter/dongle.

·         Make sure images are embedded in the PowerPoint file and not just the links.

·         Make sure the computer has enough charge (or preferably is plugged into AC).

·         If you use a microphone/speaker system, test it before the talk. Know where the on-switch is. Many microphones are very directional: a podium microphone will work really poorly if you do not speak at it; a microphone clipped onto your cloths will not work well if you turn your head.    


Presenting the talk

·         Speak loudly and articulately.

·         Exude self-confidence. Stand up straight, smile.

·         Exude excitement about your chosen research topic.

·         Ask real and rhetorical questions to keep people actively engaged.

·         Speak towards the audience. If you speak towards the screen people cannot hear you well.

·         It may help you getting started with your talk if you write out the first few lines of your talk (PowerPoint notes). You get eased into giving your talk by simply reading these notes off.

·         However, never read the whole talk off. Try not to read your slides verbatim. Do not write out your talk up and read it to you audience.

·         Get oriented about your own slides from the screen and not from the computer in front of you.

·         Look towards the audience most of the time. Try to make eye contact with people in the audience. If that makes you too nervous, then look at the projection screen.

·         Keep track of the time: find the clock in the room. Most seminar rooms or class rooms have a clock in the back of the room exactly for that purpose. Of course every computer has a clock. Do not check your wristwatch, unless you have it sitting on the podium..   

·         Do not block the audience's view of the screen. Position yourself to one side of the projector screen (unless you are walking to the screen to point at it by hand).

·         On graphs you should explain the axis. For example: “...this graph shows how distance, d,  depends on time, t. On the vertical axis I plot distance in meters and on the x-axis shows time in hours....”. This gives the listener some time to digest the graph.

·         Do not meta-comment on your speaking, e.g. avoid phrases such as, “I guess I'm running out of time; I'll just go through this quickly”.

·         Never talk beyond your allotted time. Do not take make your talk go into the question section, this is considered to be a faux pas.

·         Similar to the beginning, plan the words at the end of your talk carefully. End your talk with “thank you”, this is the cue for the audience to applaud.


The question and answer section:

The question section is 5 minutes. You can find out by the number of questions that are being asked how understandable and interesting your talk was. Getting many questions usually reflects positively on your talk.

·         Generally the person that asks a question does you a favor; make them feel good (as well as your audience); you can do this by saying “this is a good question” (even though the questing may reflect that the asker did not understand something...).

·         Do not worry about “difficult” questions.  It is unlikely to get really difficult questions, since you are probably have more knowledgeable about the topic than any other person in the room.

·         If you do not understand a question you may want to rephrase in your words and then attempt to answer the latter. You may also state that a question is difficult to answer. Indicate if you are guessing/speculate about the answer.

·         Do not get into an argument with the questioner.

·         It can be embarrassing if there are no questions. (You can avoid that by having a friend in the audience asking a question you told your friend to ask...) You can also, somewhere in the middle of your talk, leave a question and say: “ you can ask me about that later”.  

·         Anticipate possible questions and prepare some backup slides that you place in the same PowerPoint-file past your summary slide.  


How to handle stage fright:

Everyone gets this. It is a physiological reaction and may even help you (remember the adrenaline helps you think...).

·         Relax, if you have done all above preparation you are on autopilot.

·         Rehearsing your talk is the best way to reduce this anxiety.

·         Breathe deeply, it calms you down.



References: How to Give an Effective Talk, Job talk