Can bacteria be killed by purely physical trauma?
My (limited) understanding is that it is quite hard to avoid killing some bacteria even with very gentle physical manipulation. On the other hand, it is quite hard to use physical force to achieve reasonable level of sterilization. Let's bring some examples with a few (hastily found) references.
Pressure
My guess is that most examples the OP mentions (hit with a hammer, knife) will exert their biggest effect on bacteria through a peak in pressure - bacteria are comparable in size to width of a moderately sharp knife edge and thus there will be more &quot;crushing&quot; than &quot;cutting&quot; even with a knife (Science of Sharp discusses that Chosera 1k - a very good stone - will sharpen a knife to 0.5 μm, Wiki has bacteria at 0.5 - 5 μm).
I recently collaborated on a project where initial interpretation of results was wrong simply because putting a glass slip over a sample to inspect it under a microscope caused around 10% of bacterial (B. subtilis) cells to die. Putting a small weight on the slip resulted in roughly 80kPa additional pressure applied and ~ 80% of the cells dying within 25 minutes. But 80% death rate won't do much to e.g. reduce risk of food poisoning - as long as there are nutrients, bacteria will regrow quickly.
As m4rio mentions in a comment to another answer, and in line with The effect of high pressure processing on the microbial, physical and chemical properties of Valencia and Navel orange juice you need to ramp up the pressure to 100s of MPa to achieve high efficacy. And even that may not work so cleanly - e.g., the linked paper mentions that after applying 600 MPa, bacteria regrew to detectable levels after 4 weeks of storage at 4°C. Killing all (or almost all) bacteria is just really hard.
Because it was fun, I'll also link to study showing that High pressure-processed guacamole (4 cycles, 689 MPa, 5 min each) is clean enough to not spoil for 30 days in 25°C.
Note: the two sources above were linked from a commercial vendor of high-pressure products and may thus be biased. While the exact numbers might be problematic, I think the main point is unlikely to be affected.
A review High-pressure processing – effects on microbial food safety and food quality mentions some limitations, e.g.:

Endospores tend to be extremely HPP resistant compared with vegetative cells, withstanding treatments of more than 1000 MPa


ascospores of heat-resistant moulds such as Byssochlamys, Neosartorya and Talaromyces are generally considered to be extremely HPP resistant

It should however be noted that it seems that high-pressure treatment is good enough to be semi-commonly used as the main sterilization for suitable foodstuffs - Current status and future trends of high-pressure processing in food industry reports high-pressure treatment to be FDA approved and USD 10 billion worth of food being treated as of 2015.
Pressure for killing cells previously briefly discussed at Can bacteria or other microorganisms be killed by applying pressure?
Ultrasound
While frequently used for cell lysis in lab, it also doesn't kill all cells. For example The Sterilization of Suspensions Contaminated with MicroorganismsUsing Ultrasound Irradiation reports that roughly 20-30% of bacteria (Bacillus) survived 60 minutes of ultrasound treatment.
Ball mill
This is probably closest to actual &quot;physical trauma&quot; - you put small beads and a suspension with microorganisms into a cylinder and roll it hard. A low energy process for the recovery of bioproducts from cyanobacteria using a ball mill discusses using this process to extract proteins from cyanobacteria. They don't report absolute number of cells killed, just that it varies considerably with the rotation speed, size of beads, .... My interpretation is that in most cases a non-negligible proportion of the cells survive while majority is killed (and their contents extracted for further use).