Did Buddha know the properties and behaviour of the matter fully?

This question, similar to some answers, is lost in materialism. About materialism, the Thai monk Buddhadasa Bhikkhu said:

People language is used by the ordinary people who don't understand Dhamma very well and by those worldly people who are so dense that they are blind to everything but material things. Then, there is the language which is spoken by those who understand reality (Dhamma), especially those who know and understand reality in the ultimate sense. This is another kind of language

Buddhadasa

Therefore, before I make an effort to answer this question from the Pali suttas, I recommend to read the very excellent book by Buddhadasa Bhikkhu called Two Kinds of Language. Reading this books can save from lots of headaches.

In respect to the Pali suttas:

1. The term "lokavidu" or "knower of the world" is a title of the Lord Buddha (which real Buddhists chant with morning & evening Pali chanting). The suttas say:

Here, bhikkhus, a Tathāgata appears in the world, an Arahant, a Fully Enlightened One, possessing perfect knowledge and conduct, a sublime one, a world-knower (lokavidū), an unsurpassed leader of persons to be tamed, a teacher of devas and humans, an enlightened one, a Lord. He teaches Dhamma that is good at the outset, good in the middle and good at the end, with its correct meaning and wording, and he proclaims the holy life in its fulfilment and complete purity.

Iti 84

2. About the meaning of "lokavidu", Iti 112 provides some answers, as follows:

Bhikkhus, the world has been fully understood by the Tathāgata; the Tathāgata is released from the world. The origin of the world has been fully understood by the Tathāgata; the origin of the world has been abandoned by the Tathāgata. The cessation of the world has been fully understood by the Tathāgata; the cessation of the world has been realized by the Tathāgata. The course leading to the cessation of the world has been fully understood by the Tathāgata; the course leading to the cessation of the world has been developed by the Tathāgata.

Bhikkhus, in the world with its devas, māras and brahmās, with its recluses and brahmins, among humankind with its princes and people, whatever is seen, heard, sensed, cognized, attained, sought and reflected upon by the mind—that is fully understood by the Tathāgata: therefore he is called the Tathāgata.

3. The terms (above) "origin of the world" & "cessation of the world" refer to the conceptual world of "beings" or "identity" (called "birth") created by ignorance & craving; as explained in SN 12.44, as follows:

And what is the origination of the world? Dependent on the eye & forms there arises eye-consciousness. The meeting of the three is contact. From contact as a requisite condition comes feeling. From feeling as a requisite condition comes craving. From craving as a requisite condition comes clinging. From clinging as a requisite condition comes becoming. From becoming as a requisite condition comes birth. From birth as a requisite condition, then aging & death, sorrow, lamentation, pain, distress & despair come into play. This is the origination of the world.

... And what is the ending of the world? Dependent on the eye & forms there arises eye-consciousness. The meeting of the three is contact. From contact as a requisite condition comes feeling. From feeling as a requisite condition comes craving. Now, from the remainderless cessation & fading away of that very craving comes the cessation of clinging. From the cessation of clinging comes the cessation of becoming. From the cessation of becoming comes the cessation of birth. From the cessation of birth, then aging & death, sorrow, lamentation, pain, distress, & despair all cease. Such is the cessation of this entire mass of stress & suffering. This is the ending of the world.

That the word "birth" ("jati") refers to the conceptual creation of ideas of this & that "category" ("nikaye") of "beings" ("satta") based on the manifestation & use of their aggregates is clearly explained in SN 12.2, SN 23.2, SN 5.10, MN 98, MN 86 & elsewhere. For example, a set of aggregates that manifests itself by wearing a uniform, using a gun & acting to kill enemies is conceptually called a "soldier", or more often these days, "a terrorist". Or a woman that uses her womb & breasts to bear & feed children is called "a mother".

Therefore, when Iti 112 refers to "devas, māras, and brahmās, with its recluses and brahmins, among humankind with its princes and people", this refers to the categories of categorized beings based on the activities (kamma) of these various sets of five aggregates. In other words, the Buddha understands the kamma of individual life forms. This is one meaning of "knower of the world".

In addition, because all of the above "beings" are "mentally born" from their own ignorance & craving, the Buddha knows each of these beings born of self-view will suffer because of their attachment & self-view. This is another meaning of "knower of the world", namely, knowing how suffering arises & how suffering ceases. In AN 4.45, similar to SN 12.44, the word "loka" or "world" is used synonymously with the word "dukkha"("suffering").

4. In short, "the world" refers to that which is low, mundane & ordinary. The Dhammapada says:

167. Follow not the vulgar way; live not in heedlessness; hold not false views; linger not long in worldly existence.

168. Come! Behold this world, which is like a decorated royal chariot. Here fools flounder, but the wise have no attachment to it.

169. Blind is the world; here only a few possess insight. Only a few, like birds escaping from the net, go to realms of bliss.

Lokkavagga

Thus, a Pali word used about the higher teachings, such as the teachings about Emptiness , is "lokuttara", which means "beyond/transcending the world", as follows:

Thus you should train yourselves: 'We will listen when discourses that are words of the Tathagata — deep, deep in their meaning, transcendent (lokuttara), connected with emptiness — are being recited. We will lend ear, will set our hearts on knowing them, will regard these teachings as worth grasping & mastering.' That's how you should train yourselves.

SN 20.7

5. In summary, the Pali word "loka" or "world" does not necessarily refer to the physical world or physical universe, which some materialistic translators translate as "the cosmos". Yes, it is that embarrassing at times. As merely one example, in MN 79, the here-&-now meditation states called "jhana" are called "a world of exclusively pleasant feelings (ekantasukhassa lokassa )". Or, in MN 35.135, "heaven" & "hell" simply refer to agreeable & disagreeable sense experiences at the eyes, ears, nose, tongue, body & mind.

6. Since all of the above "worlds" are impermanent, the term "the world" also is used to refer to impermanence & decay, as follows. It follows this is another meaning of "knower of the world".

'The world, the world' it is said. In what respect does the word 'world' apply?

"Insofar as it disintegrates, monk, it is called the 'world.' Now what disintegrates? The eye disintegrates. Forms disintegrate. Consciousness at the eye disintegrates. Contact at the eye disintegrates. And whatever there is that arises in dependence on contact at the eye — experienced as pleasure, pain or neither-pleasure-nor-pain — that too disintegrates.

SN 35.82.

7. To end, hopefully the above is sufficient although more can probably be written about the terms "loka" ("the world") and "lokavidu" ("knower of the world").

How did Buddha fully understood the world and proclaimed it without the knowledge of all experiments of science? Was his knowledge about the properties and the behavior of matter limited?

The Buddha spent countless lives cultivating/perfecting Sila/Samadhi/Panna and evolved into an advanced being far far ahead of us run-of-the-mills on the evolutionary scale, hence able to see the limitation of experiments and sciences. Dr. Neil deGrasse Tyson gave a pretty good analogy here

The Buddha was a scientist of the mind, and had achieved full knowledge (science) of the nature of mind, which encompasses (as a subset) all 'physical' appearances, perceptions, conceptions, apperceptions, etc. He was not a physicist, a chemist, a biologist, or any of the other subdivisions of modern knowledge of the qualities, characteristics, and behaviors of the appearances. He wasn't interested in those fields. He was interested in the mind, and thus, how all these modern subjects of study arise, and how our reactions/responses to them cause us suffering. Modern scientists, even those studying the brain, do not study mind. Instead, they assume mind and brain are equivalent, or at least 100% aligned, so that what can be known about the brain, and its functioning, completely defines mind. The Buddha would disagree. The video below of the Dalai Lama, a strong supporter of science, with researchers in the field of secular meditation and its benefits and dangers, succinctly presents this divide between the Buddhist understanding of mind, and modern scientists confusion about the brain. Note the Dalai Lama's repeated questioning to the researchers "What mind? What is mind?"

Modern science's understanding of Mind is limited at best.

The Mind and Life Dialogues XXIV: Latest Findings in Contemplative Neuroscience, at The Mayo Clinic, Rochester MN 2012 https://vimeo.com/69253042

If you want further clarification of this, please see my article "The Irreconcilable Divide Between Scientists and Traditional Meditation" https://medium.com/tranquillitys-secret/the-irreconcilable-divide-between-scientists-and-traditional-meditation-c3ef9fa6e58f?source=friends_link&sk=71b0a7ac6a109437ae5d37776563eab4

phi·los·o·phy
/fəˈläsəfē/

noun

the study of the fundamental nature of knowledge, reality, and existence.

Buddha fully knows the fundamental nature of knowledge (mind), reality, and existence. Fundamental nature is how things are / how things work in principle, in general, fundamentally.

This includes the nature of causation, the nature of phenomena, events, and objects, their arising, morphing, and cessation, the nature of mind, and the functioning of mind.

This also includes the ontological foundations of ethics - why certain things are good and others are bad, and what actions lead to what results.

Buddha does not have to know all the trivial details like the exact octane number of the gasoline his car is fueled with, or how to install a spare tire, in order to be the Buddha.

No, the Buddha lived in an age where things such as germs, atoms, nuclei, molecules, thermodynamics, neurology, etc. were unknown. This is largely irrelevant to Buddhism, though there are similarities in their values and approach.

Science attempts to create theories and experiments that are independent of the human range of senses and way of thinking. The best example is quantum mechanics, which is beyond both our sensory range and our intuition. Science is therefore objective and experimental in nature.

Buddhism is a path to seeing the true nature of things through the human perspective, in particular the mind. It is therefore anthropocentric and experiential. Trying to describe or analyze the path is counterproductive, it is to be esperienced.

Joshu asked Nansen: ‘What is the path?’

Nansen said: ‘Everyday life is the path’.

Joshu asked: ‘Can it be studied?’

Nansen said: ‘If you try to study, you will be far away from it’.

The question then remains, does attaining Nirvana/Kensho/Satori render a complete understanding of the laws of physics, chemistry, biology, psychology, neurology, etc? The answer is no. While this attainment does give the practitioner a new (and very important) understanding about the one-ness, interconnectivity, and emptiness of all phenomena, it does not endow with knowledge equal to or beyond the body of science.

Again, this is not central or essential to Buddhism, just like it is not essential to know about thermonuclear reaction to feel the warmth of the sun on your face, or to know neurology to lift your arm. It is possible to experience Mind without understanding Mind. The (mythical) discourse between Bodhidharma and the Chinese emperor illustrates this very well:

The emperor asked: “What is the ultimate meaning of the holy truths of Buddhism?”

“Vast emptiness, no holiness,” replied Bodhidharma.

“Who stands here before me?” asked Emperor Wu.

“I do not know” said Bodhidharma.

The question “Who stands here before me?” is taken as "who are you in essence, as an enlightened person?", i.e. "what is the nature of Mind"?