I am a Masters student in maths in Toronto and changed supervisors one year into my Masters program. My new supervisor was expecting me to to a PhD with him, but within two months of switching to him, I mentioned to him that I would not be pursuing a PhD. I mentioned to him that I haven't decided what to do after my Masters, as I would like to work hard on my Masters thesis and write a good thesis.
Even though I said this, I am spending half my time learning data science because I would like to transition to data science after my Masters. The fact that I have only been putting in a minimal amount of effort to my thesis is reflected in the amount of work I complete every week before my meeting with him.
I have recently decided to fly to Chicago for a networking event in data science, which means that I will not be on campus for one working day of the week and also I will miss my supervisor's group meeting. I have already mentioned this to the course instructor for which I am a TA this term and he's switched my office hours for next week.
Now, the course instructor and my supervisor are in the same research group, and I am afraid to ask my supervisor for a leave for one day because I have been putting in a minimal amount of effort for my Masters thesis.
Should I ask my supervisor for a one-day leave, or should I not tell him and miss the group meeting and just return to work the next day?